CA2168829C

CA2168829C - Paroxetine hydrochloride anhydrate forms a,b,c and d

Info

Publication number: CA2168829C
Application number: CA002168829A
Authority: CA
Inventors: Victor Witold Jacewicz; Neal Ward
Original assignee: SmithKline Beecham Ltd
Current assignee: SmithKline Beecham Ltd
Priority date: 1995-02-06
Filing date: 1996-02-05
Publication date: 1997-12-16
Anticipated expiration: 2016-02-05
Also published as: SI9600036A; NL1002248C2; AU4332896A; NO960472D0; CN1636993A; SI21923B; JPH08245620A; LV11618B; CN1090187C; AR036856A2; NO20015070L; JPH11228571A; IL117035A0; SE9600406L; NZ280943A; AT407528B; GR1002466B; WO1996024595A1; IE80500B1; DE69631298T2

Abstract

The present invention relates to paroxetine hydrochloride anhydrate substantially free of bound propan-2-ol, several forms of the above, processes for preparing the above, new intermediates useful in preparing the above and methods of treating and/or preventing certain diseases by administering the compounds of the invention to a sufferer in need thereof.

Description

i ' ~16~829 NOVEL COMPOUNDS

The present invention relates to novel col~o~llds, to processes for ~le~)~ing them and to 5 their use in treating medical disorders.
EP-B-223403 (Beecham Group plc) describes paroxetine hydrochloride hemihydrate and its use in treating certain mç-lic~l disorders. Example 8 in this document describes the pl~al~ation of paroxetine hydrochloride anhydrate as platelets m.olting at 118~C and with IR
bands at 890, 1200, 1490, 3400 and 3640cm-l, by cryst~ tion from a water-col-t~ining solvent. This material is hereinafter referred to as Form Z. Subsequent repetition of the alion descrihe~ in Example 8 has failed to yield any type of paroxetine hydl~chloride anhydrate, and there is no clear teaching elsewhere in the docum~-nt of any ~ltern~tive route or ification to the process which would gene,~le the anhydrate.
Paroxetine hydrochloride anhydrate is also ~ul~ulled to be (1isclosed in the Tntern~ti~nal Journal of Ph~rm~ceutics 42, (1988) 135 to 143, publi~he~1 by Elsevier. The anhydrate is said to be produced by cryst~llising paroxetine hydrochloride from anhydrous propan-2-ol. Subsequent repetition of this process has resulted in a propan-2-ol solvate of paroxetine hydrochloride. That is to say that there is bound propan-2-ol in the product. This bound propan-2-ol cannot be removed by conventional drying techniques such as vacuum oven drying.
Paroxetine hydrochloride anhydrate subst~nti~lly free of bound propan-2-ol, has not been describe~ in the lilel~lule, nor has any method been disclosed which would yield such a product as an inevitable result. A method for ~repa,ing paroxetine hydr~chloritle anhydrate subst~nti~lly free of bound propan-2-ol has now been found. Furthermore, surprisingly, four new forms of paroxetine hydrochloride anhydrate have been found as have processes for their ~lion.
These forms are hereinafter referred to as A, B, C and D respectively. The characterising data for the Forms A, B, C and D do not correspond to the characterising data provided in Example 8 of EP-A-223403.
Accordingly, the present invention provides paroxetine hydrochloride anhydrate subst~nti~lly free of bound propan-2-ol.
The present invention also provides paroxetine hydrochloride anhydrate subst~n~i~lly free of bound organic solvent.
The present invention also provides paroxetine hydrochloride anhydrate subst~nh~lly free of propan-2-ol with the proviso that it is other than Form Z.

~16~29 Subst~nti~lly free of bound organic solvent is to be inltl~rel~d to be less than the amount of propan-2-ol which would remain solvated, i.e., bound, within the crystal lattice of the product under convenhon~l vacuum oven drying conditions.
The present invention also provides paroxetine hydrochloride solvates other than the propan-2-ol solvate as precursors in the p~ ion of paroxetine hydrochlon~e anhydrate svb~ lly free of bound organic solvent. Examples of such solvates include solvates from alcohols (other than propan-2-ol) such as propan-1-ol and eth~nol; solvates from organic acids such as acetic acid; solvates from organic bases such as pyridine; solvates from nitriles such as a~etor.;l.ile; solvates from ketones such as acetone; solvates from ethers such as tetrahydlc,rulan and solvates from chlorinated hydrocarbons such as chlor~fol,ll and solvates of hy~oc~l,olls such as toluçn~
Preferably, paroxetine hydrochloride anhydrate subst~nh~lly free of bound propan-2-ol is provided in subst~nh~lly pure form. Suitably, paroxetine hydrochloride anhydrate subst~nh~lly free of bound propan-2-ol is provided with a purity of the paroxetine hydroc~lori~le anhydrate -of greater than 50%, preferably greater than 60%, more preferably greater than 70%, yet more preferably greater than 80% and even more preferably greater than 90%. Most preferably the paroxetine hydrochloride anhydrate is provided in subst~nti~lly pure form, i.e., paroxetine hydrochloride anhydrate substantially free of bound propan-2-ol is greater than 95% pure.
It should be understood that the present invention comprising paroxetine hydochloride anhydrate substantially free of bound propan-2-ol may contain unbound water that is to say water which is other than water of cryst~ tion.
Typically the amount of bound organic solvent on a weight for weight basis would be less than 2.0%, preferably less than 1.8%, more preferably less than 1.5%, even more preferably less than 1.0%, yet more preferably less than 0.5% and most preferably less than 0.1%.

Generally, all percentages indicated herein are on a weight for weight basis unless otherwise stated.
~Ç~ ,d forms of paroxetine hydrochloride anhydrate subst~nti~lly free of bound propan-2-ol or substantially free of bound organic solvent include;
i) paroxetine hydrochloride anhydrate in Form A; (as hereinafter defined) ii) paroxetine hydrochloride anhydrate in Form B; (as hereinafter defined) iii) paroxetine hydrochloride anhydrate in Form C; (as hereinafter defined) iv) paroxetine hydrochloride anhydrate in Form D; (as hereinafter defined) ' 2168829 .

The forms of paroxetine hydrochloride anhydrate may be distinguished from each other and the material formed as a result of carrying out the procedures m~nhol~e~l in EP-B-0223403 and the Int~rn~tion~l Journal of Pharmaceutics 42, (1988), 135 to 143, by crystalline shape, S solvent analysis or techniques such as IR, melting point, X-ray diffraction, NMR, DSC, mi~;losc~y and any other analytical techniques which dirrt;l~;nliate one form from another.
For example, Form A substantially free of solvent may be distinguished from other forms by the following analytical data. Form A has a m~lting point of about 123-125~C when obtained 10 in similar purity to the material described in Example 1 which may be detçrmine~ by convention~l methods such as HPLC and ~i~nific~nt IR bands (Figure 1) at about 513, 538, 571, 592, 613, 665, 722, 761, 783, 806, 818, 839, 888, 906, 924, 947, 966, 982, 1006, 1034, 1068, 1091, 1134, 1194, 1221, 1248, 1286, 1340, 1387, 1493, 1513, 1562, 1604, 3402, 3631 cm~l.
The DSC exotherm, measured at 10~C per minute shows a ~ ul,l at about 126~C
using an open pan and a maximum at about 121~C using a closed pan. Form A also has a substantially similar X-ray diffractogram to that shown in Figure 4, for ex~mple there are characteristic peaks at 6.6, 8.0, 11.2, 13.1 degrees 2 theta and a substantially similar solid state NMR spectrum to that shown in Figure 7 for example with characteristi~. peaks at 154.3, 149.3, 141.6, 138.5 ppm.
Form B subst~nti~lly free of solvent may be distinguished from other forms by the following analytical data, i.e.it has a melting point of about 138~C when obtained in similar purity to the m~teri~l described in Example 7 which may be ~letermine~l by convendonal methods such as HPLC and si~nifiç~nt IR bands (Figure 2) at about 538, 574, 614, 675, 722, 762, 782, 815, 833, 884, 925, 938, 970, 986, 1006, 1039, 1069, 1094, 1114, 1142, 1182, 1230, 1274, 1304, 1488, 1510, 1574, 1604, 1631 cm~l.
The DSC exotherm, measured at 10~C per minute, shows a lll~illlulll of about 137~C in both open and closed pans. Form B also has a substantially similar X-ray diffractogram to that shown in Figure 5, for example, there are characteristic peaks at 5.7, 11.3, 12.4, 14.3 degrees 2 theta and a subst~ntially similar solid state NMR spectrum to that shown in Figure 8, for example with characteristics peaks at 154.6, 148.3, 150.1, 141.7, 142.7, 139.0 ppm.
Form C may be distinguished from other forms by the following analytical data, i.e. it has a melting point of about 164~C when obtain in similar purity to the material described in Example 8 which may be determined by conventional methods such as HPLC and has ~ignific~nt IR bands (Figure 3) at about 540, 574, 615, 674, 720, 760, 779, 802, 829, 840, 886, 935,965,984, 1007, 1034, 1092, 1109, 1139, 1183, 1218, 1240, 1263, 1280, 1507, 1540, 1558, 1598, 1652 cm~l.

' 2168829 The DSC exotherm, measured at 10~C per minute, shows a ma,~hllulll of about 161~C in both open and closed pans.
Form C also has a substan~ially similar X-ray diffractogram to that shown in Figure 6, for S example there are chara~t~ tis peaks at 10.1, 12.1, 13.1, 14.3 degrees 2 theta and a s~lbst~n~ially similar solid state NMR spectrum to that in Figure 7, for example with characteristic peaks at 154.0, 148.5, 143.4, 140.4 ppm.
Form D may be distinguished from other forms by the following analytical data in that it exists as a semi-crystalline solid with a melting point of about 125~C when obtained in similar purity to the material described in Example 14 which may be determined by conventional m~tho~s such as HPLC.

Form D may also be characterised in that it has essçntially similar physical characteristics when pl~,palGd from a toluene precursor solvate using methods generally described herein said toluene precursor solvate having significant IR bands at about 1631, 1603, 1555, 1513, 1503, 1489, 1340, 1275, 1240, 1221, 1185, 1168, 1140, 1113, 1101, 1076, 1037, 1007, 986, 968, 935, 924, 885, 841, 818, 783, 760, 742, 720, 698, 672, 612, 572, 537 and 465 cm-l, and characteristic X-ray diffraction peaks at 7.2, 9.3, 12.7 and 14.3 degrees 2 theta.
The question of which particular form a particular sample of paroxetine hydrochloride anhydrate is would be readily determined by one skilled in the art using conventional techniques with l-,rcle.lce to the data provided above that given in the examples and any other conventional means.
Preferably forms A and B exist as needles ad form C exits as needles or prisms.
The present invention also provides a process for the ~lep~aLion of paroxetine hydrochloride anhydrate substantially free of propan-2-ol which comprises cryst~ ing paroxetine hydrochloride in either;
i) an organic solvent or mi~Lulc of organic solvents which form a solvate with the paroxetine hydrochloride and which are not removable by conventional drying techniques; or ii) an organic solvent or Illi~Ule or organic solvents which do or do not form a solvate with the paroxetine hydrochloride but which are removable by conventional vacuum oven drying;
th~ ârLel in the case of i) displacing the solvated solvent or solvents using a displacing agent and in the case of ii) by removing the solvent.
The present invention also provides a process for the l,l~ala~ion of the paroxetine hydrochloride solvates other than the propan-2-ol solvate which comprises cryst~llising 216~829 paroxetine hydrochloride in an organic solvent om~ e of solvents which form a solvate with the l)a~e~ine h ydlocl loride and which are not removable by conventional drying techniques.
The present invention also provides a process for the p~ep~on of paroxetine S hydlochloride anhydrate s~lbst~nti~lly free of bound organic solvent which comprises ~li~l~f ing the solvated solvent or solvents from a paroxetine hydrochloride solvate using a displacing agent.
In one plerell~d aspect of the invention cryst~ tion of paroxetine hydr~çhl~ride10 anhydrate is achieved by cont~ting a solution of paroxetine free base in an organic solvent or solvents with dry hydrogen chloride gas.
~ lttom~tively, prior to the cryst~ ation of the paroxetine hydrochloride water may be removed by azeotropic ~ till~tion. Suitable solvents therefore include those which form an 15 azeotrope with water such as pyridine and propan-2-ol. It should also be appreciated that mib~ ,S of solvents can also be used to aid the azeotropic removal of water.
Thus, in another aspect of the invention paroxetine hydrochloride anhydrate is cryst~ e~ by dissolving paroxetine hydrochloride hemi-hydrate in an appl~liate solvent 20 s~1bst~nti~11y free of water which forms an azeotrope with water. Suitably solvent is removed by till~tion and fresh solvent substantially free of water is added until all of the water is removed.

Paroxetine hydrochloride hemi-hydrate or the free base thereof may be pl~al~,d according to the ~locedules generally outlined in EP-B-0 223403.
The organic solvents should be subst~nti~lly free of water to the extent that there is in~llffisient water present at the time of cryst~ tion to effect conversion to the hydrochloride hemi-hydrate. Organic solvents which are substantially free of water may be obtained in conventional manner. For example they can be dried using conventional techniques such as 30 drying over molecular sieves or they can be purchased.
Factors which affect which form of the product will be obtained include the particular choice of organic solvent or solvents to be used will depend upon the particular form of the product which is desired.
It should also be appreciated that the method of solvent removal also depends upon the particular form of the product which is desired.
For process variant i) it should be appreciated that an organic solvent or solvents which 40 form a solvate with the cryst~ e~l paroxetine hydrochloride and which are not removable by conventional drying techniques may be determined by a matter of routine e,~e~ r l;1~;on.
Examples of such organic solvents include, but in no way are limited to, alcohols especially aL~anols such as propan-2-ol, ethanol and propan-1-ol; organic acids such as acetic acid; organic bases such as pyridine; nitriles such as acetonitrile; ketones such as acetone; ethers such as tetrahyd~orul~n and chlorinated hydrocarbons such as chloroform.
The paroxetine hydrochloride solvate produced by process variant i) is suitably isolated and dried by conventional methods such as drying in vacuo to remove some or all of t'ne free or unbound solvent. It should be appreciated that it is preferable and unexpected that the degree of drying is controlled such that only free solvent is removed. The bound solvent is then ~i~pl~ed with a displacing agent such as water or ~,u~ ical carbon dioxide. It is possible to use other displacing agents which may be selected by means of routine e~l,e,;.~ ;on.
Preferably gaseous or liquid water may be used as a displacing agent. It is illl~C,l Lz~lt that the paroxetine hydrochloride solvate is contacted with enough water and for suffi~içnt time to displace the solvent but insufficient to cause conversion to the hydrochloride hemi-hydrate.
The alllount of water, the form of the water, eg, liquid or gaseous and the length of time which the paroxetine hydrochloride solvate is contacted with the water differs from solvate to solvate. This depends largely upon the solubility of the solvate in question.
Particular ratios of paroxetine hydrochloride solvate to water are outlined in the eY~mples hereinafter described (Examples 1, 4 to 6, 9 to 11, 13 and 15). It should be appreciated that the pyridine solvate is believed to be more soluble in water than for example the propan-2-ol solvate. Thus the use of the common ion effect when using diluted hydrochloric acid may help pl~,~ent dissolution of the solvate and subsequent conversion to the hydrochloride hemi-hydrate.
After contact with water to displace the bound solvent the product is suitably dried, for example, in vacuo at elevated lelllpelalul~,. Suitable drying may be over a ~lesicc~nt such as phosphorus pentoxide.
When ~upe~liLical carbon dioxide is used it should be appreciated that the flow rate, latul~, and ples~ulc of the carbon dioxide may be controlled to give O~Lilllulll solvent removal from the paroxetine hydrochloride solvate. Generally high ~le;,sur~ carbon dioxide may be used for example at about 2,500 psi. Elevated Lempe.~tures may also be preferably used such as between 50 to 80~C. More preferable between 55 to 75~C.
Process variant i) is preferably used to prepare Form A.
Preferably the cryst~ tion of the paroxetine hydrochloride anhydrate Form A
precursor solvate may be facilitated by the addition of seeds of paroxetine hydrochloride anhydrate Form A precursor solvate.

- ~168829 ely, seeds of paroxetine hydrochloride anhydrate Form A may be used to f~ilit~te the cryst~ tion of paroxetine hydrochloride anhydrate Form A precursor solvates.

For process variant ii) it should be appreciated that an organic solvent or ~ e of S organic solvents which does or does not form a solvate with the paroxetine hydrochloride but which is removable by conventional vacuum oven drying may be determined by a matter of routine e~ r.lltZ~;Ol~
An example of a solvent which forms a bound solvate with the paroxetine hydrochloride 10 but which is removable by conventional vacuum oven drying is toluene.
Toluene is preferably used to ~l~ale Form D.
The cryst~ tion of paroxetine hydrochloride anhydrate Form D precursor solvates may 15 be facilitated by the addition of seeds of paroxetine hydrochloride anhydrate Form D plccul~or solvates.
Seeds of paroxetine hydlocllloride anhydrate Form D may be used to facilitate the crystalli~tion of paroxetine hydrochloride anhydrate Form D precursor solvates.
Examples of solvents which do not form a bound solvate with paroxetine hydrochloride but which are removable by conventional vacuum oven drying are butan- 1 -ol and ethyl acetate.
Butan-l-ol is preferably used to prepare Form B and that butan-l-ol or ethyl acetate are 25 preferably used to ~l~are Form C.
If Form B is required this may be prepared according to or analogously to the procedures outlined in Example 7.
Preferably the use of seeds of Form B may be used to facilitate the cryst~llis~tion of Form B.
If Form C is required this may be prepared according to or analogously to the procedures outlined in Examples 8 and 12.
It should also be appreciated that the use of seeds of Form C may be used to f~cilit~te the cryst~llis~tion of Form C.
Seed crystals of Forms A, B, C and D may be prepared according to the proceduresdescribed herein or are freely available upon request to Cc.l~old~ Intellectual Property, SmithKline Beecham plc at New Frontiers Science Park, Third Avenue, Harlow, Essex, CMl9 SAW, United Kingdom. Form A is BRL 29060F; Form B is BRL 29060G; Form C is BRL

29060H; Form D is BRL 29060H. Samples of seeds of Forms A, B, C and D may also be oblained from the NCIMB, 23 St. Machor Drive, Aberdeen, AB2 lRY, Scotland, United King~lQm, .
s Paroxetine hydrochloride anhydrate subst~nti~lly free of propan-2-ol and Forms A, B, C
and D (all of which are he cinar~l referred to as the "products of the invention") can be used to treat and prevent the following disorders:
Alcoholism Anxiety Depression Obsessive Compulsive Disorder 15 Panic Disorder Chronic Pain Obesity Senile Dem.onti~
Migraine 20 Bulimia Anorexia Social Phobia Pre-Menstrual Syndrome (PMS) ~-lr~l~scent Depression 25 Trichotillom~ni~
Dy~ ymia Substance Abuse These disorders are herein after referred to as "the Disorders".
The present invention further provides a method for treating and/or preventing any one or more of the Disorders by ~lministering an effective and/or prophylactic amount of the products of the invention to a sufferer in need thereof.
The present invention further provides a pharmaceutical composition for use in the ll~ ,ql.... ....~onl and/or ~ ehlion of the Disorders which compri~es admixing the products of the invention with a pharmaceutically acceptable carrier.
.

The present invention also provides the use of the products of the invention for treating 40 and/or preventing the Disorders.

- ~168829 P31 l22 The present invention also provides the use of the products of the invention in the m~nnf~chlre of a mç~lic~m~nt for treating and/or preventing the Disorders.

~,fcll~,d disorders include depression, OCD and panic.
The compositions of this invention are usually adapted for oral ~lmini.ctration7 but form~ tions for dissolution for parental ~dmini~tration are also within the scope of this invention.
The cc,l~l~,osilion is usually presented as a unit dose composition cont~ining from 1 to 200mg of active ingredient calculated on a free base basis, more usually from 5 to 100mg, for example 10 to 50mg such as 10, 12.5, 15, 20, 25, 30 or 40mg by a human patient. Most preferably unit doses contain 20mg of active ingredient c~lclll~tç~l on a free base basis. Such a cc,l,-posilion is normally taken from 1 to 6 times daily, for example 2, 3 or 4 times daily so that the total ~lOUIIt of active agent ~lmini~tered is within the range S to 400mg of active ingredient calculated on a free base basis. Most preferably the unit dose is taken once a day.
P~,fell~d unit dosage forms include tablets or capsules.
The compositions of this invention may be form~ ted by convention~l methods of aLIli~ e such as blending, filling and colllpressing.
Suitable carriers for use in this invention include a dilutent, a binder, a disintegrant, a colouring agent, a flavouring agent and/or preservative. These agents may be utilised in conventional Illanl el, for example in a manner similar to that already used for ~ ke~d anti-depressant agents.
Specific examples of pharmaceutical compositions include those described EP-B-0-223403, and US 4,007,196 in which the products of the present invention are used as the active ingr~ ntc The following examples illustrate the present invention:

g 2168&29 Cryst~lline Paroxetine Hydrochloride Anhydrate Substantially Free of Bound Propan-2-ol (Form A) i) Paroxetine hydrochloride propan-2-ol solvate Paroxetine hydrochloride hemihydrate [150 g] was stirred with propan-2-ol [1000 ml]
and toluene [300 ml] in a round bottom flask and heated to boiling. Solvent was 10 removed by ~ till~tion, the total volume being ~A;Ilt~ined by adding fresh propan-2-ol, until the boiling point had reached approximately 82~C, inrlic~ting that all the water had been removed.
The lllib~lUl~ was allowed to cool to a~plo~ ately 50~C, when it spontaneously 15 cryst~ ed The COI te.-ls of the flask rapidly set to a thick paste which was diluted with propan-2-ol [approx. 500 ml] and stirred vigorously. The reslllting suspension was allowed to cool to approximately 30~C and filtered under vacuum, taking care to avoid the absorption of atmospheric moisture. The solvent-wet cake was dried in high vacuum over phosphorus pentoxide.
Yield of solvated paroxetine hydrochloride 151 g, propan-2-ol content 13.0% (estim~ted by NMR).
The infra-red spectrum (Nujol mull) showed inter alia a characteristic band at 667 cm~1.
ii) Paroxetine hydrochloride anhydrate (Form A) Paroxetine hydrochloride propan-2-ol solvate [110 g, propan-2-ol content 13.0%] was stirred in a beaker with water [275 ml] for 20 minl1tes The ~ ule was filtered under 30 vacuum and the damp solid dried in vacuum over phosphorus pentoxide to constant weight.
Yield of paroxetine hydrochloride anhydrate Form A 91.0 g Water content 0.13% (KF), propan-2-ol content 0.05% (es~ ed by NMR).
Melting point: 123-125~C
The DSC exotherm, measured at 10~C per minute, showed a maximum at about 126~C
40 using an open pan and a maximum at about 121~C using a closed pan.
The infra-red spectrum [Nujol mull] showed inter alia characteristic bands at 665, 3631 and 3402 cm~1 (see Figure 1).
45 F.1em-~nt~1 analysis:

~168829 Requires for paroxetine hydrochloride anhydrate: C 62.38 H 5.79 N 3.83%
Found: C 62.10 H 5.89 N 3.67%
The sample was also eY~mined by X-ray powder diffraction (see Figure 4) and solid state 5 C13 NMR (see Figure 7).

10 Paroxetine Hydrochloride Propan-2-ol Solvate Paroxetine free base (42.09 g) was dissolved in propan-2-ol (Fisons SLR grade, 210 rnl).
Hydrogen chloride gas was bubbled into a cooled flask co~ g propan-2-ol (157 g) until 20.8 g hydrogen chloride had been absorbed. 39 g of this solution (cont~ining 15 a~ ely 4.6 g hydrogen chloride) was added rapidly to the paroxetine solution and the llli,~lU~ stirred briskly. After about 1 minute cryst~ tion began and the ~ ule rapidly set to an unsLill~ble paste, which was allowed to stand for one hour. The product was collected by filtration, washed with propan-2-ol (50 ml) and dried under vacuum at ~mhient ~ u~e to constant weight in a desicc~tor cont~ining phosphoric oxide. The 20 ~mple was analysed by NMR spectrometry and found to contain a~plc ~i,llately 6%
propan-2-ol by weight. Part of the sarnple was placed in a vacuum oven set at 50~C and further dried to const~nt weight, which took a further 4 days. NMR spectrometry showed that the sarnple contained a~)p~ tely 2% propan-2-ol by weight.

Par~ ;. e Hydrochloride Propan-2-ol Solvate Paroxetine free base (52.37 g) was dissolved in dry propan-2-ol (250 ml) and a solution 30 of hydrogen chloride gas in dry propan-2-ol (50 g of solution, containing approximately 5.8 g hydrogen chloride) was added rapidly with brisk stirring. After about 30 seconds cryst~llis~tion commenced, and the ,llh~Lule was stirred for a further 30 minlltes at ~mbient te,l~ dlule to permit complete cryst~ tion. The product was isolated by ~acuulll filtration, washed with 25 ml dry propan-2-ol, and dried in a ~lesi~c~tQr 35 conl~ini.-g phosphoric oxide at ambient tell~p~ldture under vacuum.
After 3 days a sample was analysed by NMR and found to contain 10.5% propan-2-ol.
The rest of the material was dried for a further 3 days to constant weight under vacuum with fresh phosphoric oxide in the desiccator. NMR analysis showed that the product 40 contained 5.7% w/w propan-2-ol.

P31122 ~168829 EXAMPLE 4, Crystalline Paroxetine Hydrochloride Anhydrate Substantially Free of Bound Pyridine (Form A) s i) ~p~alion of paroxetine hydrochloride pyridine solvate Paroxetine hydrochloride conl~ining ca. 2% propan-2-ol [20.0g] was dissolved in hot pyridine [200 ml] and some of the solvent removed by ~ till~tion The flask was sealed 10 and allowed to cool, wh~ on the pale red solution spontaneously cryst~llise~l The thick sllspersion was stirred well, filtered, avoiding excessive exposure to atmospheric moi~ re, and the solid washed on the filter with pyridine [25 ml]. The product was dried under high vacuum over phosphorus pentoxide.
15 Yield 22.0 g.
Microscopic ey~min~tion showed the product to be in the form of needle crystals, and analysis by NMR showed the presence of 15.2% by weight of pyridine ~theory for a 1:1 solvate 17.77%). The infra-red spectrum (Nujol mull) of the pyridine solvate differed 20 from both that of hernihydrate and anhydrate Forrn A and in particular showed no sipnifi~nt bands in the 3000 cm-l region. The pyridine solvate also gave a distinctive X-ray powder diffraction pattern.
ii) Preparation of paroxetine hydrochloride anhydrate (Form A) Paroxetine hydrochloride pyridine solvate [5.00 g] was added to 5 molar hydrochloric acid [25 ml] in a beaker and stirred for 5 minutes. The l~lixlule was filtered, drained well, and washed with water [15 ml]. The crystals were dried under high vacuum over phosphorus pentoxide.
Yield 4.00 g The infra-red spectrum (Nujol mull) was consistent with paroxetine hydrochlorideanhydrate Form A, and no pyridine could be detected by NMR analysis.

Paroxetine Hydrochloride Anhydrate SubsPnti~lly Free of Bound Acetic Acid (Form A) c~d~ion of paroxetine hydrochloride acetic acid solvate Paroxetine hydrochloride containing approximately 2% propan-2-ol [30.0g] was dissolved in hot glacial acetic acid [ 120 ml] and some of the solvent removed by 45 tlistill~tion. The flask was sealed and allowed to cool overnight. The clear pale yellow solution was seeded with paroxetine hydrochloride anhydrate Form A, ultrasonicated and n stirred at room ~ ,1GIU1~ for several hours. The mi~Lure was allowed to stand for 24 hours, filtered and the product dried under high vacuum in a tiesicc~t'~r cont~ining pot~ccinm hydroxide.
5 Yield 17.29 g.
Analysis by NMR showed the presence of 13.5% by weight of acetic acid (theory for a 1:1 solvate 14.10%). The infra-red spectrum (Nujol mull) of the acetic acid solvate differed from both that of paroxetine hydrochloride hemihydrate and anhydrate Form A
10 and in particular showed a strong band at 1705 cm~l indicative of bound acetic acid and no signific~nt bands in the 3000 cm~ 1 region. The acetic acid solvate also gave a distinctive X-ray powder diffraction pattern.
ii) Prep~r~tion of paroxetine hydrochloride anhydrate (Form A) Paroxetine hydrochloride acetic acid solvate [1.00 g] was treated with 5 molar hydrochloric acid [5 ml] and stirred for 5 minutes. The ~ ure was filtered, drained well, and the crystals dried under high vacuum in a desicc~tor cont~ining phosphorus pentoxide.
Yield 0.80 g The infra-red spectrum (Nujol mull) conrll.-led that the product was paroxetine hydlvcl-lorifls anhydrate Form A. Analysis by NMR showed the presence of 25 a~r~i...ately 0.4% acetic acid. Microscopic ex~min~tion showed the material to be in the form of fragmented needles.

30 Par~ e Hydrochloride Anhydrate Sl-bst~nti~lly Free of Bound Acetonitrile (Form A) i) ~al~lion of paroxetine hydrochloride aceloniLIile solvate 35 Paroxetine hydrochloride anhydrate Form A plepa~ed using the method of Example 1 (10.8 g) was dissolved in warm anhydrous acetonitrile (40 ml) in a conical flask, sealed, and cooled in the refrigerator for 1 hour, during which time some crystals separated. The was ultrasonic~ted ~ ull.cd to the refrigerator7 and left overnight. The con~ntsset to a thick paste. The following morning the paste was broken up using vigorous 40 ~h~king and ultrasonication, and the lni~ule filtered. The product was dried under high vacuum in a desiccator con~ining phosphorus pentoxide.
Yield 9.30 g, ace~onillile content 2.5% (by NMR).
45 ii) Preparation of paroxetine hydrochloride anhydrate (Form A) Paroxetine hydrochloride acetonitrile solvate (4.23 g) was stirred in water (20.6 g) for 10 min~ltes The solid was collected by vacuum filtration, washed on the filter with water (10 ml) and dried in a vacuum oven cor,t~ining phosph-orus pentoxide at 50~C.
5 Yield 3.75 g The IR ~e~t. Ulll showed that the product was paroxetine hydrochloride anhydrate Form A.
10 Acelolli~ ile content app~ ately 0.5% (by NMR).

15 Pa~ Hydrochloride Anhydrate (Form B) Paroxetine free base [10.0 g] was dissolved in butan- 1 -ol [25 ml] at room lelllpcl~ture and a solution of hydrogen chloride gas [1.25 g] in butan-l-ol [15 ml] was added. The clear pale red/brown solution was sealed and stored in the refrigerator overnight. A
20 small amount of crystalline material formed on the base of the flask and ultrasonic~tion was used to bring about cryst~ tion of the buLk. The llli~lu c was again stored in the refrigerator overnight, then allowed to warm to room temperature and filtered. The product was dried under high vacuum in a ~esicc~tQr cont~ining phosphorus pentoxide.
25 Microscopic eY~min~tion with a polarising microscope showed the sample to be in the form of feather shaped crystals.
Melting point: 137-138~C
30 The NMR (CDC13) spectrum conforrned to that of a standard sample of paroxetine hydrochloride.
The elemell~l analysis was consi~tent with anhydrous paroxetine hydrochloride:
Required for ClgH21NClFO3: C 62.38 H 5.79 N 3.83 Cl 9.69%
Found: C 62.08 H 5.75 N 3.81 Cl 9.62%
The X-ray powder diffractogram confirrn~ that the sample was crystalline (see Figure 5). The diffractogram differed from both that of hemihydrate and anhydrate Form A.
The IR spectrum (Nujol mull) also differed from both that of hemihydrate and anhydrate Form A (see Figure 2).
The DSC exotherm, measured at 10~C per minute, showed a m~imulll at about 137~C in both open and closed pans.

- 216~829 .

The sample was also examined by solid state C13 NMR (see Figure 8).

5 Paroxetine Hydrochloride Anhydrate (Form C) Paroxetine l~yd~ loride hemihydrate [300 g] and toluene [1200 ml] were heated under reflux and the water removed using a Dean and Stark apparatus. When no further water could be collected, the bulk of the toluene was removed by ~ t~ tion and replaced with 10 anhydrous butan-1-ol. Di~till~tion was continued until the still te.~ ture reached about 117~C, indic~ting that all the toluene had been removed. The l~lixlule was diluted to about 1200 ml with butan-1-ol and allowed to cool. At about 42~C, seeds of paroxetine hydrochloride anhydrate Form B (needles) were added. Although cryst~ tiol then began, it was observed that the product was in the form of well15 formed prisms, in-lir~ting that the product was crystallising in a dirr~,e.~t form to the seeds added.
The i~lur~ was allowed to stand overnight, then filtered. The crystals were washed on the filter with butan- 1-ol, then dried in vacuum at S0~C over phosphorus pentoxide.
Yield 250 g Meltingpoint: 162-164~C
25 Analysis by NMR (CDC13) confirmed that the product was paroxetine hydrochloride and showed the presence of a trace of butan- 1-ol (ca 0.1% by weight ). The infra red spectrum (Nujol mull) dirr~r~ from either Form A or B, (see Figure 3).
Water content 0.06% (KF) The elc ,.~ l analysis was consi~tent with anhydrous paroxetine hydrochloride:
RequiredforC1gH21NClFO: C62.38 H5.79 N3.83 C19.69%
Found: C 62.23 H 5.67 N 3.83 C1 9.74%
The DSC exotherm, measured at 10~C per minute, showed a maximum at about 161~C in both open and closed pans.
The X-ray powder diffractogram confirmed that the sample was crystalline (see Figure 40 6). The diffractogram differed from both that of anhydrate Form A and anhydrate Form B.
The sarnple was also examined by solid state C13 NMR (see Figure 9).

- ~168829 Paroxetine Hydrochloride Anhydrate S--bst~nti~lly Free of Bound Acetone (Form A) i) Paroxetine Hydrochloride Acetone solvate Paroxetine free base (10.51 g) was dissolved in acetone (40 ml, dried with 4A molecular sieves), and a solution of hydrogen chloride gas (1.31 g) in dry acetone (10 ml) added with stinin~ Cryst~ tion occurred ~ontaneously within one minute, and the ~ Lulci quickly beca~ u-l~ able. After appr~xilllalely half an hour the product was filtered, 15 placed in a ~esi~c~tor over phosphorus pentoxide, and dried at ambient temperature overni ~ht Weight of product: 11.24 g. Acetone content (estim~t~ by NMR) 4% wt/wt. The infra-red spectrum showed a characteIistic band at 667 cm~ 1.
Ap~r~ a~ely half the product was placed in a vacuum oven set at 50~C and dried further to constant weight. NMR analysis of the resulting product intli~tçd the presence of 1.2% acetone wt/wt.
25 ii) Paroxetine Hydrochloride Anhydrate (Form A) A sample of the acetone solvate (5.18 g) was stirred for 10 minutes in water (20 ml), filtered, and dried at 50~C in a vacuum oven cont~ining phosphorus pentoxide.
Weight of product: 4.63 g. NMR analysis indicated the presence of 0.6% acetone wt/wt.
The infra-red spectrum corresponded to the spectrum of paroxetine hydrochloride anhydrate Form A and showed a characteristic band at 665 cm~ 1.

Paroxetine Hydrochloride Anhydrate S~lbst~nti~lly Free of Bound Ethanol (Form i) Paroxetine Hydrochloride Ethanol Solvate Paroxetine free base (11.25 g) was dissolved in absolute ethanol (40 ml), and a solution of hydrogen chloride gas (1.9 g) dissolved in absolute ethanol (20 ml) added with sti~in~ There was no sign of cryst~ tion after 10 minlltes~ so the clear solution was seeded with paroxetine hydrochloride anhydrate Form A. After 30 minutes there was still no sign of cryst~ tion, so the solution was evaporated at reduced pressure to a~ o~lllately half volume and re-seeded. This time slow crystallisation was observed, '~ P31122 2168829 and the ~ ulc was left for a further hour. The resulting crystalline mass was dried at ~mbient l~m~ ture in a vacuum desiccator coll~nillg phosphorus pentoxide.
Weight of product: 11.87 g. Ethanol content testim~te~l by NMR) 4% wt/wt. The infra-red spectrum showed a characteristic band at 667 cm~1.
A small sample was placed in a vacuum oven set at 50~C and dried further. NMR
analysis of the resulting product indic~te~ the presence of 0.7% ethanol wt/wt. The infra-red spectrum collG~ onded to the spectrum of paroxetine hydrochloride anhydrate Form A and showed a characteristic band at 665 cm~ 1.
ii) Paroxetine Hydrochloride Anhydrate tForm A) A sample of the ethanol solvate (5.3 g) was stirred for 10 minutes in water (20 ml), filtered, and dried ovemight at arnbient ~elllp~ e in a desiccator cont~ining phosphorus pentoxide.
Weight of product: 4.56 g. NMR analysis indicated the presence of less than 0.4%ethanol wt/wt. The infra-red spectrum colresponded to the spe~ ulll of paroxetine hydrochl~ri(le anhydrate Form A and showed a ch~racteristic band at 665 cm~l.

Paroxetine Hydrochloride Anhydrate S--bst~nti~lly Free of Bound Chloroform (Form A) i) Paroxetine hydrochloride chloroform solvate Paroxetine free base (8.54 g) was dissolved in chlolvfollll (30 ml), and a solution of hydrogen chloride gas (1.05 g) dissolved in chloroform (10 ml) added with stirring.
There was no sign of cryst~ tion after 5 minutes, so the clear solution was seeded with paroxetine hydrochloride anhydrate Form A. After 15 minutes there was still no sign of cryst~ tion, so hydrogen chloride gas was bubbled through the solution until theorange colour disappeared. After one hour signs of very slow cryst~ tion could be seen, with large needle crystals visible to the eye. The mixture was left to crystallise in a ~l~pel~d flask for a further hour, then filtered and dried at ambient ~ llp~.-atUl~; in a vacuum desicc~tor containing phosphorus pentoxide.
Weight of product: 5.65 g. Chloroform content (estim~ted by NMR) 12.5% wt/wt. The infra-red spectn~m showed a characteristic band at 667 cm~ 1.
A small sample was placed in a vacuum oven set at 50~C and dried further. NMR
analysis of the resulting product indicated the presence of 3.4% chlorofc,llll wt/wt.
ii) Paroxetine hydrochloride anhydrate (Form A) ~ ~168829 A ~ample of the chloroform solvate containing 12.5% chloroform (2.0 g) was stirred for 10 .~ es in water (8 ml), filtered, and dried overnight in a vacuum oven at 50~C.
Weight of product: 1.09 g. NMR analysis in-lic~tet3 the presence of a~~ ill.ately 0.8%
chlol~rc)llll wt/wt. The infra-red spectrum corresponded to the spectrum of paroxetine 5 hydrochlQnde anhydrate Form A and showed a characteristic band at 665 cm~l.

Paroxetine Hydrochloride Anhydrate (Form C) Paroxetine free base (8.5 g) was dissolved in ethyl acetate (40 ml) and hydrogen chloride gas was bubbled in until the weight of the flask and cor,lellls had increased by 1.1 g.
There was no sign of cryst~llis~tion after 15 minutes, so the clear solution was seeded with paroxetine hyL~chloride anhydrate Form A. After stirring for a further one hour, 15 signs of very slow cryst~llis~tion could be seen. The mixture was left stirring overnight to crystallise in a slo~p~ ,d flask, then filtered and dried at ambient lel~elalu c; in a vacuum ~esicc~tor cont~ ing phosphorus pentoxide.
Weight of product: 7.56 g. Ethyl acetate content (estimated by NMR) 0.4% wtlwt. The 20 infra-red spectrum was different from both paroxetine hydrochloride hemihydrate and anhydrate Form A and consictent with the infra-red spectrum obtained in E~mple 8.

25 Paro~tine Hydrochloride Anhydrate Substantially Free of Bound Propan-l-ol (Form A) i) P~ala~ion of paroxetine hydrochloride propan-l-ol solvate 30 Paroxetine free base [10.6 g] was dissolved in propan-l-ol [30 ml] and hydrogen chloride gas (1.25 g) passed into the solution. The warm solution was seeded with paroxetine hydrochloride anhydrate Form B and ultrasoni~ted, whe~.lpon the pale red solution - rapidly cryst~llise~ The thick suspension was diluted with propan-l-ol (25 ml), filtered avoiding excessive e~o~ulc to atmospheric moisture, and the product dried in vacuum 35 over phosphorus pentoxide.
Yield 10.3 g.
Analysis by NMR showed the presence of approximately 7% by weight of propan-l-ol.
40 The infra-red spectrum (Nujol mull) showed that the product was not Form B, but a solvated species with a significant band at about 667 cm~ 1. The propan- l-ol solvate also gave a distinctive X-ray powder diffraction pattern.
ii) Preparation of paroxetine hydrochloride anhydrate (Form A) 21~8829 P31 1~22 Paroxetine hydrochloride propan-l-ol solvate [5.24 g] was stirred in water [25 ml] for 10 ,..;n-J~eS The ~ LUlC was filtered and the product washed with water [10 ml]. The crystals were dried in high vacuum over phosphorus pentoxide at 50~C.
5 Yield 4.35 g The infra-red spectrum (Nujol mull) confirmed that the product was the anhydrate Form A. Analysis by NMR showed the presence of ca 0.25% by weight of propan-l-ol.

Paroxetine Hydr~ ride Anhydrate ~Form D) ala~ion of paroxetine hydrochloride toluene solvate Paroxetine hydrochloride hemihydrate [100 g] was stirred under reflux in toluene [1000 ml] and the water removed using a Dean and Stark apparatus. The solution was allowed to cool, seeded with paroxetine hydrochloride Form A, and ultrasonicated. Cryst~llis~tion was not in~luce~l, but after sti~ing for 40 minutes at room temperature the contents of the flask suddenly set to a thick 20 paste. The product was collected by filtration and dried in vacuum over phosphorus pentoxide.
Analysis of the product by NMR showed the presence of about 10% wt/wt of toluene. The toluene solvate gave a distinctive IR spectrum, showing a characteristic band at 672 cm~l.
25 The above procedure was repeated, seeding with the toluene solvate, and the product dried in vacuum over phosphorus pentoxide.
Yield of toluene solvate 106.7 g 30 Analysis of the product by NMR showed the presence of about 10% wt/wt of toluene. The product gave a distinctive X-ray powder diffractogram.
ii) Desolvation of the toluene solvate The toluene solvate [20.0 g] was heated for 18 hours at 80~C in vacuum over phosphorus pentoxide. Analysis by NMR showed the presence of about 0.3% wt/wt of toluene.
Water conle..l. 0.08% (KF) 40 Melting point: ca 125~C

' 2168829 P3ll~

Paroxetine Hydrochloride Anhydrate S~bst~nti~lly Free of Bound Tetrahydrofuran (Form A) s i) Paroxetine hydrochloride tetrahyd~ufulan solvate.
Paroxetine free base (10.26 g) was dissolved in dry tetrahyd~ufu,ail (35 ml), and a solution of hydrogen chloride gas (1.3 g) dissolved in dry tetrahy&ufulan (15 ml) added 10 with brisk sti~in~ After a short period when the solution r~m~in~1 clear, rapid cryst~ holl co.. ~ ced so that within a few minutes the llli~lule became unstirrable.
After a further half hour, the product was collected by filtration and dried at ambient teml)~ alur~ in a vacuum ~lesicc~tQr containing phosphorus pentoxide.
Weightofproduct: 12.31 g. Tetrahy~ûfulan content (es~ by NMR) 11.4% wt/wt.
The infra-red spectrum showed a characteristic solvate band at 667 cm~1.
A small sample was placed in a vacuum oven set at 50~C and dried over the weel~n~l NMR analysis of the reslllting product indicated the presence of 1.3% tetrahy~oruldn wt/wt.
ii) Paroxetine hydrochloride anhydrate (Form A) A sample of the tetrah~dlorulan solvate conl~ il-g 11.4% tetrahyd~ful~n (5.0 g) was stiIred for 10 minutes in water (20 ml), filtered, and dried in a vacuum oven at 50~C.
Weight of product: 3.79 g. NMR analysis indicated the presence of a~,lo~ alely 0.02%
tetrahy~ fuu ~ wt/wt. The infra-red spectrum corresponded to the spectrum of paroxetine hydrochloride anhydrate Form A and showed a characteristic band at 665 cm~ 1 Paroxetine Hydrochloride Anhydrate S~bst~nti~lly Free of Bound Propan-2-ol (Form A) Paroxetine hydrochloride propan-2-ol solvate (70 mg, cont~ining 11.6% propan-2-ol) (Examples 2 or 3) was treated with a stream of carbon dioxide (3 mVminute, 55~C and 2,500 psi). After 30 minutes the propan-2-ol content was reduced to 5.2%, and after a total of 120 minutes it was further reduced to 0.4%. The temperature was then raised to 75~C, and after 30 minutes the propan-2-ol content was found to be 0.13%. After a further 60 minutes at 75~C the propan-2-ol content was 0.07%.
In a se~Le e~pe. ;.-~ent 70 mg of propan-2-ol solvate was extracted with carbon dioxide (3 mVminute 75~C and 2,500 psi). After 150 minutes the propan-2-ol content was found to be 0.19%.

This e~ l~nt was repeated on a larger sample of the solvate (350 mg) under the same con-li~ion~, and the propan-2-ol content was found to be 0.16% after 150 minlltes s Crystq~ qtior~ of paruA~ le hydrochloride anhydrate Form C from 2-butanone by ~J~ ~
Paroxetine hydrochlonde anhydrate Form C [7.0 g] was heated to boiling in anhydrous 2-10 butanone [40 ml] and the solution allowed to cool to ca 40~C. Seeds of Form C were added and tne stirred ll~i~lure allowed to cool to room le-"pel~ture. The product was collected by filtration, washed with anhydrous 2-butanone [20 ml] and dried in an oven at 100~C.
Weight of dried product 5.95 g Melting point: 162 -163~C
The infra-red spectrum (Nujol mull) was consistent with paroxetine hydrochloride anhydrate Form C.

CrystqllicqtiQn of paroxetine hydrochloride from toluene by see~lin~
25 Paroxetine hydrochloride anhydrate Form C [20.0 g] was dissolved in boiling toluene [200 ml]
and a~,~f~ llately 50 ml of the solution added to each of 4 conical flasks. Each flask was heated again to boiling, allowing some toluene vapour to reflux out, in order to remove seeds.
Flask 1 was imm~i~tely sealed with a ground glass stopper and set aside to cool. The ~c...~ ng flasks were sealed with foil, and allowed to cool somewhat, before adding seed crystals as 30 follows:
Flask 2 was seeded with paroxetine hydrochloride toluene solvate Flask 3 was seeded with paroxetine hydrochloride anhydrate Form B
Flask 4 was seeded with paroxetine hydrochloride anhydrate Form C
The added seeds remained undissolved. The flasks were sealed with ground glass ~lu~e.~, stirred gently for a few seconds then set aside to cool. Flask 2 was observed to crystallise very 40 readily, while in Flasks 3 and 4 crystallisation took place more slowly. At this point Flask 1 rem~ine~ completely clear, and all 4 flasks were left at room le"lpeldture ovemight The following morning Flask 1 contained only a few crystals, while Flasks 2, 3 and 4 had extensively cryst~ e~

' - ~168~29 Flask 1 was stirred gently for several hours, during which time the bulk of the paroxetine hyd~ l lori~e cryst~llice l The product from each flask was collected by filtration and dried at 50~C under vacuum.
Flask 1 (not seeded) Weight of product: 4.25 g A~peal~ ce: short needles/rods Infra red spectrum: conci~tçnt with paroxetine hydrochloride anhydrate Form C
Meltingpoint: 161- 162~C
Flask 2 (seeded with toluene solvate) Weight of product: 3.80 g Ap~al~ce: long fine needles Infra red spectrum: consi~tent with paroxetine hydrochloride toluene solvate Solvent content: 11% wt/wt toluene by NMR
Melting point: initial melt at about 70~C, followed by resoliflification and further melt at 161 - 162~C
Flask 3 (seeded with anhydrate Form B) Weight of product: 4.20 g Appeal~lce: needles Infra red spectrum: consistent with paroxetine hydrochloride anhydrate Form B
Solvent content: 0.8% wt/wt toluene by NMR
Melting point: 138 - 140~C

P311~

Flask 4 (seeded with anhydrate Form C) s Weight of product: 4.93 g A~pedlance: needles Infra red spectrum: consi~tent with paroxetine hydrochloride anhydrate Form C
Solvent cOIlh.lL; 0.8% wt/wt toluene by NMR
Melting point: 161 - 162~C
Example 19 Crystalline Paroxetine Hydrochloride Anhydrate Subst~nti~lly free of Bound Propan-2-ol (Form A) Vacuum oven dried paroxetine hydrochloride propan-2-ol solvate conLdining 2.6% propan-2-ol (1 g) was placed in a glass tube. The tube was immersed in a water bath set at 50~C and nitrogen gas, saturated with water vapour at a temperature of 40~C, was passed through the sample. After 10 hours a small sample was removed an analysed by NMR, which showed that 25 the level of propan-2-ol had fallen to 2.0%. The temperature of the bath surrounding the tube was increased to 80~C, and the len~e. ature at which the gas being passed through the sample was saturated was increased to 70~C. After 10 hours the contents of the tube were sampled again and analysed by NMR, which showed that the level of propan-2-ol had fallen further to 1.0%.
F.Y~ le 20 Paroxetine Hydrochloride Anhydrate Substantially Free of Bound Acetone (Form A) 35 i) l~le~alaLion of paroxetine hydrochloride acetone solvate A sllspen~ion of paroxetine hydrochloride anhydrate Form C (prisms) (5.0 g) in acetone (75 ml) was heated to boiling to give a mass of fine nçe~lles. The flask was sealed and allowed to stand overnight at room t~ lpeldture. The solvent was removed at low ~lllp~ture using a rotary 40 evaporator and replaced by hexane (100 ml). The solvent was again removed at low temperature to give the acetone solvate as a crystalline residue. Analysis by NMR showed the presence of acelone (12.2% by weight), and the IR spectrum (Nujol mull) showed characteristic bands at 667 and 1714 cm -1.

~ P311~ ~16~829 .
ii) ~a~ation of paroxetine hydrochloride anhydrate (Form A) from the acetone solvate Paroxetine hydrochloride Form C (5.3 g) was converted to the acetone solvate by a similar S p.~cedul~, to that described above. Water (50 ml) was added, and the resulting snspen~iQn shaken gendy for 10 ~~;nu~es. The white solid was collected by filtration, drained thoroughly and dried in a vacuum oven at 50 ~C. Yield 4.60 g. Acetone content (NMR) 0.1% by weight.
The IR s~ecl- Ulll (Nujol mull) conforrned to that of a standard sample of paroxetine hydroc-hloride anhydrate Forrn A.
Example 21 Paroxetine Hydrochloride Anhydrate Form D
15 i) p~ alion of paroxetine hydrochloride toluene solvate.
An anll~dlous solution of paroxetine hydrochloride in toluene was ple~al~,d by refluxing a llli~lu~e of paroxetine hydrochloride hemihydrate in toluene in a Dean and Stark app~lus until no more water could be collected. The solution was allowed to cool and seeded with paroxetine 20 hydrochloride toluene solvate. The product was collected by filtration, washed with toluene and dried in a vacuum oven at 50 C. Analysis by NMR showed the presence of 18% by weight of toluene. The infra-red spectrum, recorded at 22 ~C using a Perkin-Elmer 1720X FT-IR
specllullle~e~ coupled to a Spectra-Tech IR-Plan microscope, is shown in Figures lOA and lOB.
25 ii) preparation of paroxetine hydrochloride anhydrate Form D.
A small sample of paroxetine hydrochloride toluene solvate (toluene content 18% wt/wt) was heated at 80 ~C and the paroxetine hydrochloride anhydrate Form D produced e~r~minsd by infra-red microspec~lulllell y using a Perkin-Elmer 1720X FT-IR specll. l"etel coupled to a 30 Spectra-Tech IR-Plan microscope. The resulting infra-red spectrum is shown in Figures 1 lA and llB.

Claims

1. Paroxetine hydrochloride anhydrate substantially free of bound propan-2-ol.

2. Paroxetine hydrochloride anhydrate substantially free of bound organic solvent.

3. Paroxetine hydrochloride anhydrate substantially free of bound propan-2-ol with the proviso that it is other than Form Z.

4. Paroxetine hydrochloride solvates other than the propan-2-ol solvate.

5. Paroxetine hydrochloride solvates as defined in claim 4 wherein the solvate is selected from the group consisting of alcohols (other than propan-2-ol), organic acids, organic bases, nitriles, ketones, ethers, chlorinated hydrocarbons and hydrocarbons.

6. Paroxetine hydrochloride solvate as defined in claim 4 wherein the solvate is selected from the group consisting of propan-1-ol, ethanol, acetic acid, pyridine, acetonitrile, acetone, tetrahydrofuran, chloroform and toluene.

7. Paroxetine hydrochloride anhydrate substantially free of bound propan-2-ol insubstantially pure form.

8. Paroxetine hydrochloride anhydrate as defined in claim 1 in Form A; which is characterised in that it has a melting point of about 123-125°C when obtained in similar purity to the material described in Example 1 and has significant IR bands (Figure 1) at about 513, 538, 571, 592, 613, 665, 722, 761, 783, 806, 818, 839, 888, 906, 924, 947, 966, 982, 1006, 1034, 1068, 1091, 1134, 1194, 1221, 1248, 1286, 1340, 1387, 1493, 1513, 1562, 1604, 3402, 3631 cm-1 and the DSC exotherm, measured at 10°C per minute shows a maximum at about 126°C
using an open pan and a maximum at about 121°C using a closed pan; it also has a substantially similar X-ray diffractogram to that shown in Figure 4, including characteristic peaks at 6.6, 8.0, 11.2, 13.1 degrees 2 theta and a substantially similar solid state NMR spectrum to that shown in Figure 7 including with characteristic peaks at 154.3, 149.3, 141.6, 138.5 ppm.

9. Paroxetine hydrochloride anhydrate as defined in claim 1 in Form B; which is characterised in that it has a melting point of about 138°C when obtained in similar purity to the material described in Example 7 and has significant IR bands (Figure 2) at about 538, 574, 614, 675, 722, 762, 782, 815, 833, 884, 925, 938, 970, 986, 1006, 1039, 1069, 1094, 1114, 1142, 1182, 1230, 1274, 1304, 1488, 1510, 1574, 1604, 1631 cm-1; the DSC exotherm, measured at

10°C per minute, shows a maximum of about 137°C in both open and closed pans; it also has a substantially similar X-ray diffractogram to that shown in Figure 5, including characteristic peaks at 5.7, 11.3, 12.4, 14.3 degrees 2 theta and a substantially similar solid state NMR

spectrum to that shown in Figure 8, including characteristics peaks at 154.6, 148.3, 150.1, 141.7, 142.7, 139.0 ppm.
10. Paroxetine hydrochloride anhydrate as defined in claim 1 in Form C; which is characterised in that it has a melting point of about 164°C when obtain in similar purity to the material described in Example 8 and it has significant IR bands (Figure 3) at about 540, 574, 615, 674, 720, 760, 779, 802, 829, 840, 886, 935, 965, 984, 1007, 1034, 1092, 1109, 1139, 1183, 1218, 1240, 1263, 1280, 1507, 1540, 1558, 1598, 1652 cm-1; the DSC exotherm, measured at 10°C per minute, shows a maximum of about 161°C in both open and closed pans;
it also has a substantially similar X-ray diffractogram to that shown in Figure 6 including characteristic peaks at 10.1, 12.1, 13.1, 14.3 degrees 2 theta and a substantially similar solid state NMR spectrum to that in Figure 7, including characteristic peaks at 154.0, 148.5, 143.4, 140.4 ppm.

11. Paroxetine hydrochloride anhydrate as defined in claim 1 in Form D; which is characterised in that it exists as a semi-crystalline solid with a melting point of about 125°C
when obtained in similar purity to the material described in Example 14 and Form D is also characterised in that it has essentially similar physical characteristics when prepared from a toluene precursor solvate using methods generally described herein said toluene precursor solvate having significant IR bands at about 1631, 1603, 1555, 1513, 1503, 1489, 1340, 1275, 1240, 1221, 1185, 1168, 1140, 1113, 1101, 1076, 1037, 1007, 986, 968, 935, 924, 885, 841, 818, 783, 760, 742, 720, 698, 672, 612, 572, 537 and 465 cm-1, and characteristic X-ray diffraction peaks at 7.2, 9.3, 12.7 and 14.3 degrees 2 theta.

12. Paroxetine hydrochloride anhydrate as defined in claim 8, which is in the form of needles.

13. Paroxetine hydrochloride anhydrate as defined in claim 9, which is in the form of needles.

14. Paroxetine hydrochloride anhydrate as defined in claim 10, which is in the form of needles or prisms.

15. A compound as defined in any one of claims 1 to 3 which is selected from the group consisting of; crystalline paroxetine hydrochloride anhydrate substantially free of bound pyridine (Form A), paroxetine hydrochloride anhydrate substantially free of bound acetic acid (Form A), paroxetine hydrochloride anhydrate substantially free of bound acetonitrile (Form A), paroxetine hydrochloride anhydrate (Form B), paroxetine hydrochloride anhydrate (Form C), paroxetine hydrochloride anhydrate substantially free of bound acetone (Form A), paroxetine hydrochloride anhydrate substantially free of bound ethanol (Form A), paroxetine hydrochloride anhydrate substantially free of bound chloroform (Form A), paroxetine hydrochloride anhydrate (Form C), paroxetine hydrochloride anhydrate substantially free of bound propan-1-ol (Form A), paroxetine hydrochloride anhydrate (Form D), and paroxetine hydrochloride anhydrate substantially free of bound tetrahydrofuran (Form A).

16. A process for the preparation of paroxetine hydrochloride anhydrate substantially free of propan-2-ol which comprises crystallising paroxetine hydrochloride in either;
i) an organic solvent or mixture of organic solvents which form a solvate with the paroxetine hydrochloride and which are not removable by conventional drying techniques; or ii) an organic solvent or mixture or organic solvents which do or do not form a solvate with the paroxetine hydrochloride but which are removable by conventional vacuum oven drying;
thereafter in the case of i) displacing the solvated solvent or solvents using a displacing agent and in the case of ii) by removing the solvent.

17. A process for the preparation of the paroxetine hydrochloride solvates other than the propan-2-ol solvate which comprises crystallising paroxetine hydrochloride in an organic solvent or mixture of solvents which form a solvate with the paroxetine hydrochloride and which are not removable by conventional drying techniques.

18. A process for the preparation of paroxetine hydrochloride anhydrate substantially free of bound organic solvent which comprises displacing the solvated solvent or solvents from a paroxetine hydrochloride solvate using a displacing agent.

19. A method for treating and/or preventing any one or more of the Disorders by administering an effective and/or prophylactic amount of the products of the invention to a sufferer in need thereof.