DEF0010665MA - - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

. Registration date: December 19, 1952. Advertised on December 1, 1955

GERMAN PATENT OFFICE

It has been found that N-substituted carboxamides can be produced in a simple manner in this way let the isonitrones isomeric to the carboxamides rearranged by heating.

Isonitrons can, according to older proposals, for example by treating Schiff's bases with Per compounds or by mixing oxo compounds with primary amines and per compounds be won.

As isonitrones suitable for rearrangement z. B. called ethylidene isobutylamine oxide, isopropylidene butylamine oxide, n-butylidene-isopropylamine-oxide, isopropylidene-isopropylamine-oxide, n-butylidene-cyclohexylamine-oxide, Ethylidene aniline oxide, cyclopentylidene n-butylamine oxide, Cyclohexylidene methylamine oxide, di- (cyelohexylidene) ethylenediamine dioxide, cyclchexylidene cyclohexylamine oxide, Cyclopentylidtn-arilin oxide, Cyclohexylidene aniline oxide, cyclohexylidene p-toluidine oxide, Cyclohexylidene-p-chloroaniline oxide, Cyclohexylidene-m-nitroaniline-oxide, Cyclohexylidene-p-anisidine-oxide, Benzylidene-isobutylamine-oxide, Benzylidene-cyclohexylamine-oxide, a-Methylbcr.zyliden-cyclohexylamine-oxide, Benzylidene aniline oxide, p-chlorobenzylidene aniline oxide, p-nitrobenzylidene aniline oxide, Furfurylidene cyclohexylamine oxide and benzylidene benzylamine oxide.

The rearrangement can be carried out in such a way that the isonitrons are heated by themselves until the Reaction sets in. The temperature required for this depends on the constitution of the Isoni

509597/53

F 10665 IVb / 12p

Irons and can be easily closed with a simple preliminary experiment detect.

Since the heat of reaction released during the rearrangement is considerable, it is better to proceed in such a way that one the isonitrons with a suitable inert solvent diluted and brought to the required rearrangement temperature. The heat of reaction is thereby dissipated as heat of vaporization.

ICs are also possible, from the neutral raw reaction compounds that occur during the production of the isonitrons, which contain the isonitrones without going out without isolating the isonitrones.

The N-substituted carboxamides are valuable Intermediates, e.g. B. for the production of plasticizers and plastics.

example 1

The crude (yclopentylidene-aniline-oxide, obtained by treating 80 g (1/2 "mol) of cyclopentylidene-aniline (b.p. 0.4 mm 80 to 90") with 50 g ( ¹ Z ₂ mol) is heated.

Io obtain ° - 7 () "/ _o peracetic acid at 20 to - ■

has been in a 2-1 flask with attached Steigrolir on the open flame. As soon as the strongly exothermic rearrangement reaction begins, it is removed the flame. By distilling the reaction product, in which no more active oxygen can be detected is obtained at 135 to 138 / 0.6 mm 27 g of N-l'heiiylpipendoii- (2). Melting point 99 to 100 °. Yield 31 "/".

The constitution of the compound is by mixed clinking point with that by partial electrolytic reduction of N-1'henylghitarimid according to Buhei Sakurai (Chemisches Zentralblatt, 1938, II, p. 3538) obtained N-l'heiiyl]) i]) eridon- (2) secured.

C11, C IL, - C IL, - C H N - < H

Biitvliden-cvclohexylamin-oxvd

Beis] Hel 3

^{A solution of 98 g (1} Z ₂ mol) of cyclohexylidene-cyclohexylaniine oxide in 150 ecm of tetralin is brought to the boil in a 2-liter flask with an attached riser pipe, and the flame is removed after the vigorous rearrangement reaction has started. When the keaklion has ended, the reaction product is distilled. At 130 to i3.:"/o.i mm, 83 g of the N-cyclohexyl-eaprolactam, which has not yet been described, pass over

point ^ z ins 53 "· A list » ■ ute «5 ° / Ό · N 7th .17 C ₁ Ji ₂₁ ON (kj5, 3) N 7th , 26 Calculated <■ 7. 5.7 ⁽ ) H ΙΟ. 7th .33 found C 7. 5.8i H K), 7- ΙΟ, . «4 7 < ^s . «3

The rearrangement proceeds according to the following scheme:

N -

<r

Cyclopcntyliden-aniline- N-Phcnyl-

oxide piperidone- ^)

Example 2

34 g ( ¹ J ₅ mol) of butylidene-cyclohexylamine oxide (boiling point 69 ° / oi mm) are heated in a 2-liter KOI-ben with a wide stirrer until the vigorous reaction begins. The dark reaction product is then fractionally distilled. At 90 to 95% 0.8 mm, 14.5 g of a liquid fraction are obtained, and at 132 to 140%, 12.5 g of a solidifying fraction are obtained. The crystalline fraction turns out to be N-cyclohexylbutyramide due to the mixed melting point with the reaction product of butyryl chloride and cyclohexylamine. Melting point 62 to 63 ⁰ .

The liquid fraction is the N-propyl-N-cyclohexylformamide isomeric with the crystalline compound. The constitution of which is secured by the Mischsehmelzpunkt the picrate of the base obtained by saponification with 2O ° / ₀ hydrochloric acid with the picrate of the obtained by hydrogenation of N-N-propylaniline Propylcyclohexylamins. Total yield 80 ° / ₀ .

CH ₃ -CH ₂ -CH ₂

N-propyl-N-cyclohexylformamide

The compound is insoluble in water and alkalis, but easily soluble in strong mineral acids.

The rearrangement proceeds according to the following scheme:

₁₀ H ₁₉ ON

ht

C ₁₀ H ₁₉ OW (169.3)
Calculated C 70.96
pefnnd C 71.06
71.08

Calculated
found

H II .32 N 8th , 28 H II , 11 N 8th , 21 II .40 8th , 28

The rearrangement proceeds according to the following scheme:

CH ₃ -CH ₂

CH., - C-N

N-cyclohexylbutyramide

O
HC-N-

ΛΤ /

CO

IN

Cyclohexylidene-cyclo- N-Cyclohcxyl-

hexylamine oxide caprolactam

Example 4

^{A solution of 38 g (x} / ₅ mol) of cyclohexylidene-aniline is heated in a flask with a reflux condenser

597/53

F 10665 IVb / 12 p

oxide (melting point 75 ⁰ ) in 100 ecm xylene until the rearrangement reaction begins. As soon as the reaction has ended, the solvent is removed in vacuo and N-phenylcaprolactam is obtained as a dark, crystallized mass in practically quantitative yield. It can be purified either by recrystallization or by vacuum distillation.

Example 5

^{A solution of 22.4 g (1} Z ₁₀ mol) of cyclohexylidenep-chloroaniline oxide (melting point 70 °) in 50 ecm of xylene is heated in a flask with a reflux condenser until the rearrangement reaction begins. The dark reaction product is then fractionally distilled in vacuo. At 170 to 17370.8 mm, N- (p-chlorophenyl) -caprolactam, which has not yet been described, is obtained as a crystalline solidifying fraction which, after recrystallization from light gasoline, melts at 68 to 69 °. Yield 18'g (80%).

C ₁₂ H ₁₄ ONCl C. (223.7) H 6.31 N 6.26 Calculated C. 64-43 H 6.63 N 6.58 found 64.84 6.48 6.51 64.92

Example 6

Heating the crude cyclohexylidene-aniline-oxide, obtained by treating 87 g ⁽¹ Z ₂ moles) of cyclohexylidene-aniline with 50 g ⁽¹ Z ₂ moles) of 76 ° / _o peracetic acid at - has been io ° received - to 20 , in a 2 l flask with an attached riser pipe over a free flame and allows the violent rearrangement reaction to proceed. If the dark reaction product is subjected to fractional distillation, 33 g of N-phenylcaprolactam, which has not yet been described, are obtained at 158 to 16072 mm. Yield 35 ⁰ Z ₀ . Melting point 74 to 75 ⁰ .

C ₁₂ H ₁₅ ON (189.3) H 7.99 N 7.40 Calculated C 76.15 H 8.15 N 7.36 found C 76.03 8.17 7.48 76.17

If you work in the representation of the isonitrone at an even lower temperature, e.g. B. at - 50 to - 70 ^0, is obtained after the rearrangement, the N-Phenylcaprolactam in 50 ° / _o yield.

Example 7

The crude cyclohexylidene-p-toluidine oxide, which has been obtained by reacting 43 g ( ¹ Z ₄ mol) of cyclohexylidene-p-toluidine with 25 g ( ¹ Z ₄ mol) y6 ° figy peracetic acid at -20 to -10 °, is heated , for relocation in an i-1 flask with an attached riser pipe over a free flame. Distillation in vacuo gives 28 g of the N- (p-tolyl) -caprolactam, which has not yet been described, in _a yield of 55% at 140 to 14570.4 mm. Melting point 53 to 54 °.

C ₁₃ H ₁₇ ON (203.3) H 8.43 N 6.89 Calculated C 76.81 H 8.87 N 6.99 found c 77.03 8.92 7.23 77.10

Claims (1)

PATENT CLAIM: Process for the preparation of N-substituted carboxamides, characterized in that one which rearranges the isonitron isomeric isomeric to the carboxamides by heating. 1 509 597/53 11.55