IE42821B1 - Improvements in or relating to a process for the preparation of tetrahydro-thieno /3,2-c/- and /2,3-c/pyridine derivatives - Google Patents
Improvements in or relating to a process for the preparation of tetrahydro-thieno /3,2-c/- and /2,3-c/pyridine derivativesInfo
- Publication number
- IE42821B1 IE42821B1 IE1079/76A IE107976A IE42821B1 IE 42821 B1 IE42821 B1 IE 42821B1 IE 1079/76 A IE1079/76 A IE 1079/76A IE 107976 A IE107976 A IE 107976A IE 42821 B1 IE42821 B1 IE 42821B1
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- tetrahydro
- radical
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D495/00—Heterocyclic compounds containing in the condensed system at least one hetero ring having sulfur atoms as the only ring hetero atoms
- C07D495/02—Heterocyclic compounds containing in the condensed system at least one hetero ring having sulfur atoms as the only ring hetero atoms in which the condensed system contains two hetero rings
- C07D495/04—Ortho-condensed systems
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
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- Heterocyclic Carbon Compounds Containing A Hetero Ring Having Oxygen Or Sulfur (AREA)
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Abstract
PROCESS FOR THE PREPARATION OF TETRAHYDRO-THIENO3,2-C!- AND 2,3-C!PYRIDINE DERIVATIVES. This invention relates to a process for the preparation of tetrahydro-thieno 3,2-c!pyridine derivatives of the formula (Ia) and their isomeris tetrahydro-thieno 2,3-c!pyridine derivatives in which R1 represents hydrogen, a lower alkyl or alkoxy radical, an aryl radical or an aralkyl radical; R2 and R3 represent hydrogen, halogen, a lower alkyl or alkoxy group, a di(loweralkyl)amino, nitro, cyano or acetamido group or, together with the phenyl nucleus to which they are attached, form a polycyclic aromatic ring, comprising reacting a tetrahydrothieno3,2-c!pyridine derivative of the formula: (IIa) or a derivative of its isomer, tetrahydro2,3-c!pyridine, with formaldehyde H-CHO and a phenol of the formula: (III).
Description
This invention relates to a new process for the preparation of tetrahydro - thieno[3,2 - c]pyridine derivatives of the formula:
and their isomers, tetrahydrothieno[2,3 - c]pyridine derivatives of the formula:
in which the hydroxyl group OH is at 2- or 4-position; R^ represents hydrogen, a C, _ alkyl or C, , alkoxy radical, l-o 1-b an aryl radical or an aralkyl radical; and R^ represent each hydrogen, halogen, a C, r alkyl or C. , alkoxy radical -L“b X~b a di-(C, , alkyl)-amino, nitro, cyano or acetamido radical or, together with the phenyl nucleus to which they are attached, form a polycyclic aromatic ring, R2 and R^ being at 3-, 4-, 5- or 6-position when OH is at 2-position and
- 3 42831 being at 3- and 5-positions and other than hydrogen when OH is at 4-position.
Said compounds possess valuable therapeutic properties and, in addition, are useful intermediates in the preparation of derivatives used both in the chemical and pharmaceutical industries.
4,5,6,7 - Tetrahydro - thieno[3,2 - c]pyridine derivatives have already been described, together with a process for their preparation, in French Patent Specification
2,215,948. Said process comprises condensing a compound of the formula:
in which the radicals A and B represent each at least an atom or group selected from hydrogen, halogen, θ alkyl,
CL , alkoxy, nitro and amino, with a halide of the formula 1-6
Hal-R in which Hal represents a halogen atom and K represents an optionally substituted alkyl, aryl or aralkyl radical, to give a pyridinium salt of the formula:
and subsequently hydrogenating said pyridinium salt to give a derivative of the formula (1):
- 4 42821
4,5,6,7 - Tetrahydro - thieno[2,3 - c]pyridine derivatives have also been prepared by an analogous process (French Patent Specification 2,315,274).
This process, however, is expensive and delicate in that it requires numerous difficult procedures.
In addition, use of this preparative process makes it difficult to obtain derivatives having on the nitrogen atom a benzyl radical carrying a hydroxyl group at 2- or 410 position. Indeed, to obtain derivatives of such type according to said process, it is necessary to proceed via the methoxylated derivative which is subsequently hydrolyzed.
Therefore, the object of the present invention is to provide a simple process for the preparation, in good yields, of derivatives of the formula (la) or their isomers of the formula (lb) in which the phenyl nucleus carries a hydroxyl group at 2- or 4-position.
The process of this invention comprises reacting a tetrahydrothieno[3,2 - c]pyridine derivative of the formula (Ila)
4282 or a derivative o£ its isomer, tetrahydro[2,3 - cJpyridine, of the formula:
(lib)
in which has the above-described meanings, with formaldehyde H—CHO and a phenol of the formula
OH (III)
in which R^ and R^ have the above-defined meanings, to give the desired derivative of the formula. (Ia) or (Ib).
The (Mannich type) reaction occurs at one of the ij ortho-positions of the phenol, when it is free. When both ortho-positions are occupied, the reaction occurs at the para-position.
Thus, in the case of phenols in which at least one of the positions ortho to OH is free, the Mannich reaction fc occurs at said free ortho-position:
42831
radicals Rg and Rg occupying optionally 3-, 4-, 5- or 6positions in the derivative of the formula (la) or (lb).
The same reaction occurs with unsubstituted phenol, and with polycyclic phenols such as β-naphthol, for example.
In the case of phenols carrying both substituents Rg and Rg at ortho-position to the OH radical, the reaction occurs at para-position:
The condensation reaction of this invention is advantageously conducted in a medium consisting of an organic solvent such as ethanol, propanol or dioxan. The reaction is advantageously effeoted in the hot, at a temperature between 50°C and the boiling point of the solvent used, best results being obtained at temperatures
42831
-Ιοί about 80°C.
It is preferred to effect the reaction with constant stirring, during a period of time of 2—20 hours.
Formaldehyde or its different polymerization products, such as polyoxymethylene, may be used for the reaction.
Purification of the desired derivative is effected either by recrystallization from an organic solvent, or after conversion to a salt, by washing, drying and optionally recrystallization from an organic solvent.
The following non-limiting Examples are given to illustrate the present invention.
EXAMPLE 1
Preparation of 5 - (3,5 - dimethyl - 4 - hydroxy - benzyl)4,5,6,7 - tetrahydro - thieno[3,2-c]pyridine
A mixture of 4,5,6,7 - tetrahydro - thieno[3,2 - c]pyridine (6.1 g; 44 mmoles), 2,6 - dimethyl - phenol (5.4 g; 44 mmoles), polyoxymethylene (2.7 g? 90 mmoles) and dioxan (50 cc) is stirred at 80°C during 3 hours. After concentration in vacuo, the residue is recrystallized from ethanolisopropanol (M.p.=158°C; yield: 48%).
EXAMPLE 2
Preparation of 5 - (2 - hydroxy - 5 - nitro - benzyl) - 6methyl - 4,5,6,7 - tetrahydro - thieno[3,2 - c] pyridine
A mixture of 6 - methyl - 4,5,6,7 - tetrahydrothieno[3,2 - c] - pyridine (6.3 g; 41 mmoles), p - nitrophenol (5.7 g; 41 mmoles), polyoxymethylene (2.5 g; 83 mmoles) and dioxan (50 cc) is stirred at 80°C during 4 hours. After concentration in vacuo, the residue is dissolved in ether and then treated with 0.5 equivalent oxalic acid in ethanol solution. The resulting semi-oxalate is filtered, washed with boiling methanol-water (1:3),
- 8 filtered again and dried (M.p.=214°C; yield: 27%).
EXAMPLE 3
Preparation of 6 - (2 - hydroxy - 5 - chloro - benzyl) - 7methyl - 4,5,6,7 - tetrahydro - thieno[2,3 - c] pyridine
A mixture of 7 - methyl - 4,5,6,7 - tetrahydrothieno[2,3 - c] pyridine (6.0 g; 39.2 mmoles), p-chlorophenol (5.05 g; 39.2 mmoles), polyoxymethylene (2.36 g; 78.5 mmoles) and dioxan (70 cc) is stirred at 80°C during 15 hours. After concentration in vacuo, the residue is taken up into 2N hydrochloric acid. The aqueous phase is extracted with ether, made basic with concentrated ammonia and again extracted with methylene chloride. The organic extracts are washed with water, dried over sodium sulfate and concentrated in vacuo. The residue is treated with 0.5 equivalent oxalic acid in ethanol solution. The resulting semi-oxalate is filtered and recrystallized from ethanol-dimethyl formamide (M.p.=170°C; yield: 38%).
EXAMPLE 4
Preparation of 6 - (2 - hydroxy - 5 - cyano - benzyl)20 4,5,6,7 - tetrahydro - thieno[2»3 - c] pyridine
A mixture of 4,5,6,7 - tetrahydro - thieno[2,3 - c]pyridine (1 g; 7.2 mmoles), p-cyano-phenol (95% purity;
0.9 g; 7.2 mmoles), polyoxymethylene (0.43 g; 14.4 mmoles) and dioxan (20 cc) is stirred at 80°C during 4 hours. After concentration in vacuo, the residue is taken up into 2N hydrochloric acid. The aqueous phase is extracted with ether, made basic with concentrated ammonia and again extracted with methylene chloride. The organic extracts are washed with water, dried over sodium sulfate and concen30 trated in vacuo. The residue is recrystallized from isopropyl ether-isopropanol (M.p. 134°C; yield: 23%).
2 8 21
- 9 Using the procedures described in the preceding Examples, the following compounds are obtained:
EXAMPLE 5
-(2- Hydroxy - 5 - methoxy - benzyl) - 4,5,6,7 - tetrahydro - thieno[3,2 - c] pyridine.
White crystals; M.p.=90°C.
EXAMPLE 6
-(2- Hydroxy - 5 - nitro - benzyl) - 4,5,6,7 - tetrahydro - thieno [3,2 - c) pyridine.
Yellow crystals; M.p.=160°C;.
EXAMPLE 7
-(2- Hydroxy - 3 - methoxy - benzyl) - 4,5,6,7 - t-etrahydro - thieno[3,2 - c]pyridine.
White crystals,- M.p.=S4°C.
EXAMPLE 8
-(5- Chloro - 2 - hydroxy - benzyl) - 4,5,6,7 - tetrahydro - thieno[3,2 - c] pyridine.
White crystals; M.p.=82—85°C.
EXAMPLE 9
-(5- Chloro - 2 - hydroxy - benzyl) - 6 - methyl4,5,6,7 - tetrahydrothieno[3,2 - c] pyridine, semi-oxalate.
White crystals; M.p.=200°C.
EXAMPLE 10
-(5- Fluoro - 2 - hydroxy - benzyl) - 4,5,6,7 - tetrahydro - thieno[3,2 - c]pyridine.
Pale yellow crystals; M.p.=92°C.
EXAMPLE 11
- p - Hydroxybenzyl - 4,5,6,7 - tetrahydro - thieno[3,2 - c]pyridine, semi-oxalate
White crystals; M.p.=216°C.
- 10 43821
EXAMPLE 12
-(2- Hydroxy - 3 - methyl - benzyl) - 4,5,6,7 - tetrahydro - thieno[3,2 - c] pyridine, semi-oxalate, semihydrate.
White crystals; M.p.=198°C.
EXAMPLE 13
- (3- Acetamido - 2 - hydroxy - benzyl) - 4,5,6,7thieno[3,2 - c]pyridine.
White crystals; M.p.=154°C.
EXAMPLE 14
6- (5- Chloro - 2 - hydroxy - benzyl) - 4,5,6,7 - tetrahydro - thieno[2,3 - c]pyridine.
White crystals; M.p.=222°C.
EXAMPLE 15
6 - (3,4 - Dichloro - 2 - hydroxy - benzyl) - 4,5,6,7tetrahydro - thieno[2,3 - c]pyridine.
White crystals; M.p.=153°C.
EXAMPLE 16
6-(2- Hydroxy - 5 - nitro - benzyl) - 4,5,6,7 - tetra20 hydro - thieno[2,3 - c] pyridine.
Yellow crystals; M.p.=159°C.
EXAMPLE 17
- (3,5 - Dimethyl - 4 - hydroxy - benzyl) - 4,5,6,7tetrahydro - thieno[2,3 - c]pyridine.
Ivory crystals; M.p.«<118oc.
EXAMPLE 18
6-(2- Hydroxy - 3 - isopropyl - benzyl) - 4,5,6,7 - tetrahydro - thieno[2,3 - c]pyridine.
Very pale yellow crystals; M.p.=l01°C.
EXAMPLE 19
6-(2- Hydroxy - 5 - methyl - benzyl) - 4,5,6,7 - tetrahydro - thieno[2,3 - c] pyridine, semi-oxalate, semihydrate.
- 11 42821
Very pale yellow crystals; M.p.=196°C.
EXAMPLE 20
6-(4- Dimethylamino - 2 - hydroxy - benzyl) - 4,5,6,7tetrahydro - thieno[2,3 - c] pyridine.
Pink crystals; M.p.=140°C.
EXAMPLE 21
- o - Hydroxybenzyl - 4,5,6,7 - tetrahydra - thieno[2,3 - c]pyridine.
Beige crystals; M.p.=98°C.
EXAMPLE 22
- (1 - β - Hydroxynaphthyl - methyl) - 4,5,6,7 - tetrahydro - thieno[2,3 - c]pyridine.
Pale yellow crystals; M.p.=150°C.
EXAMPLE 23
- (3,5 - Dichloro - 4 - hydroxy - benzyl) - 4,5,6,7tetrahydro - thieno[3,2 - c] pyridine.
White crystals; M.p.=170°C.
It is to be noted that many of the pyridine derivatives of the formula lb above are described and claimed in our Patent Specification No. ii'/D ; .
Claims (7)
1. CIAIMSi1. Process for the preparation of tetrahydrothieno[3,
2. - c] - pyridine derivatives of the formula: in which the hydroxyl radical is at 2- or 4-position; R^ represents hydrogen, a C, _ alkyl or C, . alkoxy radical, l-o l-o an aryl radical or an aralkyl radical; R 2 and R^ each represent hydrogen, halogen, a C, r alkyl or C, , alkoxy radical, l—o l-o a difC^ θ alkyl)amino radical or a nitro, cyano or acetamido group, or, together with the phenyl nucleus to which they are attached, form a polycyclic aromatic ring, R 2 and being at 3-, 4-, 5- or 6-position when OH is at 2-position and being at 3- and 5-positions and other than hydrogen when OH is at 4-position, comprising reacting a tetrahydrothieno[3,2 - c]pyridine derivative of the formula: 4 2821 or a derivative of its isomer, tetrahydrothieno[2,3 pyridine, of the formula: ol- in which R^ has the above-defined meanings, with formaldehyde H—CHO and a phenol of the formula: OH (III) in whioh R 2 and R 3 have the above-defined meanings, to give the desired derivative of the formula (Ia) or (Ib). 10 2. Process as claimed in claim 1, wherein the reaction is effected in an organic solvent, particularly ethanol, propanol or dioxan.
3. Process as claimed in claim 2, wherein the reaction is effected at a temperature between 50°C and the boiling point of the solvent. 42831 - 14
4. Process as claimed in claim 2 or 3, wherein the reaction is effected with stirring, during a period of time of 2—20 hours.
5. Process as claimed in claim 1, substantially as 5 hereinbefore described with reference to any one of the foregoing examples.
6. A process as claimed in claim 1, substantially as herein described.
7. Compounds of formula (Xa) and (lb) as defined in 10 claim 1, whenever prepared by a process as claimed in any one of claims 1—6.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR7521549A FR2317303A1 (en) | 1975-07-09 | 1975-07-09 | PROCESS FOR PREPARING TETRAHYDROTHIENO (3,2-C) AND (2,3-C) PYRIDINE DERIVATIVES |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| IE42821L IE42821L (en) | 1977-01-09 |
| IE42821B1 true IE42821B1 (en) | 1980-10-22 |
Family
ID=9157715
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| IE1079/76A IE42821B1 (en) | 1975-07-09 | 1976-05-21 | Improvements in or relating to a process for the preparation of tetrahydro-thieno /3,2-c/- and /2,3-c/pyridine derivatives |
Country Status (26)
| Country | Link |
|---|---|
| JP (1) | JPS5236691A (en) |
| AR (1) | AR211019A1 (en) |
| AT (1) | AT348526B (en) |
| BE (1) | BE843822A (en) |
| CA (1) | CA1071634A (en) |
| CH (1) | CH609349A5 (en) |
| DD (1) | DD125081A5 (en) |
| DE (1) | DE2630474A1 (en) |
| DK (1) | DK141333B (en) |
| ES (1) | ES448404A1 (en) |
| FR (1) | FR2317303A1 (en) |
| GB (1) | GB1544093A (en) |
| GR (1) | GR59812B (en) |
| HU (1) | HU172280B (en) |
| IE (1) | IE42821B1 (en) |
| IL (1) | IL49641A (en) |
| LU (1) | LU74674A1 (en) |
| MX (1) | MX3224E (en) |
| NL (1) | NL7605362A (en) |
| PH (1) | PH12311A (en) |
| PL (1) | PL100685B1 (en) |
| PT (1) | PT65072B (en) |
| SE (1) | SE421699B (en) |
| SU (1) | SU628819A3 (en) |
| YU (1) | YU40137B (en) |
| ZA (1) | ZA763219B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5665315A (en) * | 1979-11-02 | 1981-06-03 | Nec Corp | Magnetic recording and inspecting system |
| DE3736664A1 (en) * | 1987-10-29 | 1989-05-11 | Boehringer Ingelheim Kg | TETRAHYDRO-FURO- AND -THIENO (2,3-C) PYRIDINE, THEIR USE AS A MEDICAMENT AND METHOD FOR THE PRODUCTION THEREOF |
| NZ233654A (en) * | 1989-05-18 | 1993-02-25 | Bristol Myers Squibb Co | 2-aminomethyl-5-aminophenol derivatives; hair dye compositions containing them |
-
1975
- 1975-07-09 FR FR7521549A patent/FR2317303A1/en active Granted
-
1976
- 1976-03-31 LU LU74674A patent/LU74674A1/xx unknown
- 1976-04-01 CH CH404576A patent/CH609349A5/en not_active IP Right Cessation
- 1976-04-21 GR GR50593A patent/GR59812B/en unknown
- 1976-04-23 YU YU1030/76A patent/YU40137B/en unknown
- 1976-05-06 PT PT65072A patent/PT65072B/en unknown
- 1976-05-19 NL NL7605362A patent/NL7605362A/en not_active Application Discontinuation
- 1976-05-21 IE IE1079/76A patent/IE42821B1/en unknown
- 1976-05-24 IL IL49641A patent/IL49641A/en unknown
- 1976-05-31 ES ES448404A patent/ES448404A1/en not_active Expired
- 1976-06-01 ZA ZA763219A patent/ZA763219B/en unknown
- 1976-06-03 AR AR263501A patent/AR211019A1/en active
- 1976-06-09 SU SU762366005A patent/SU628819A3/en active
- 1976-06-10 CA CA254,573A patent/CA1071634A/en not_active Expired
- 1976-06-16 MX MX000320U patent/MX3224E/en unknown
- 1976-07-01 DK DK297876AA patent/DK141333B/en not_active IP Right Cessation
- 1976-07-01 PH PH7618641A patent/PH12311A/en unknown
- 1976-07-05 AT AT489876A patent/AT348526B/en not_active IP Right Cessation
- 1976-07-06 BE BE168664A patent/BE843822A/en not_active IP Right Cessation
- 1976-07-07 DD DD193745A patent/DD125081A5/xx unknown
- 1976-07-07 SE SE7607762A patent/SE421699B/en not_active IP Right Cessation
- 1976-07-07 DE DE19762630474 patent/DE2630474A1/en active Pending
- 1976-07-08 JP JP51081441A patent/JPS5236691A/en active Granted
- 1976-07-08 PL PL1976191016A patent/PL100685B1/en unknown
- 1976-07-08 GB GB28511/76A patent/GB1544093A/en not_active Expired
- 1976-07-09 HU HU76PA00001255A patent/HU172280B/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5236691A (en) | 1977-03-22 |
| DK141333B (en) | 1980-02-25 |
| PT65072A (en) | 1976-06-01 |
| AR211019A1 (en) | 1977-10-14 |
| GR59812B (en) | 1978-03-01 |
| IL49641A (en) | 1978-08-31 |
| DK297876A (en) | 1977-01-10 |
| ZA763219B (en) | 1977-05-25 |
| IL49641A0 (en) | 1976-07-30 |
| DE2630474A1 (en) | 1977-01-13 |
| ATA489876A (en) | 1978-07-15 |
| SE7607762L (en) | 1977-01-10 |
| CA1071634A (en) | 1980-02-12 |
| DD125081A5 (en) | 1977-03-30 |
| PT65072B (en) | 1977-09-13 |
| NL7605362A (en) | 1977-01-11 |
| PL100685B1 (en) | 1978-10-31 |
| ES448404A1 (en) | 1977-07-01 |
| SE421699B (en) | 1982-01-25 |
| YU40137B (en) | 1985-08-31 |
| PH12311A (en) | 1979-01-16 |
| BE843822A (en) | 1977-01-06 |
| GB1544093A (en) | 1979-04-11 |
| YU103076A (en) | 1982-02-28 |
| CH609349A5 (en) | 1979-02-28 |
| AU1568676A (en) | 1977-03-31 |
| LU74674A1 (en) | 1976-09-01 |
| AT348526B (en) | 1979-02-26 |
| MX3224E (en) | 1980-07-28 |
| DK141333C (en) | 1980-08-25 |
| HU172280B (en) | 1978-07-28 |
| FR2317303B1 (en) | 1977-12-16 |
| FR2317303A1 (en) | 1977-02-04 |
| SU628819A3 (en) | 1978-10-15 |
| JPS5310077B2 (en) | 1978-04-11 |
| IE42821L (en) | 1977-01-09 |
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