Procédé de préparation de dérivés du cyclopentane

1330003 Cyclopentane derivatives MAY & BAKER Ltd 26 May 1971 [27 May 1970] 25486/70 Headings C2C and C2P The invention comprises novel cyclopentane derivatives of the formula wherein A is >C=O or -CH(OR3), R1 is C 1-10 alkyl, C 3-10 cycloalkyl or C 3-10 cycloalkyl- C 1-4 alkyl, m is 4 or 6, R2 is OH or OR4, N(R5)R6 or, except when A is >C=O, NHN(R5)R6, wherein R4 is C 1-4 alkyl, R5, R6, R7 and R8 each are H or C 1-4 alkyl, and R3 is H, C 1-4 alkyl, or, when R2 is OH or OR4, a group -COR9, wherein R9 is C 1-4 alkyl, and when A is -CH(OR3)- the symbols R3 both are H or identical groups and, when R2 is OH, non-toxic salts thereof. The compounds of the above formula may be prepared by one of the following methods:- (a) Compounds wherein R2 is OH and R3 is H or alkyl by the alkaline hydrolysis of the corresponding compounds in which R2 is OR4. (b) Compounds wherein A is CH(OR3), R2 is OR4, and R3 is H by the acid hydrolysis of the corresponding di-tetrahydropyranyl ethers, or by the reduction of the double bonds in compounds of the formula wherein n is 1 or 2. (c) Compounds wherein A is >C=O, R2 is OH and R3 is H by the acid hydrolysis of compounds of the formula wherein the symbols R12 are identical C 1-4 alkyl or together form an ethylene linkage unsubstituted or substituted by identical alkyl groups on each C atom. (d) The amides, hydrazides, esters and ethers are made by usual methods from the appropriate acids, esters, acid halides and free hydroxy containing compounds. Ethyl 7 - { 3 - (2 - tetrahydropyranyloxy) - 2- [3 - (2 - tetrahydropyranyloxy)octyl]cyclopentyl}- heptanoate (A) is obtained by the following reaction sequence. 1,4-Dioxa-6-(2-cyanoethyl)- spiro[4,4] - nonane -# 1,4 - dioxa - 6 - (3- oxooctyl)spiro[4,4]- nonane -# 1,4 - dioxa - 6- (3 - hydroxyoctyl)spiro[4,4]nonane -# 1,4-dioxo - 6 - (3 - acetoxyoctyl)spiro[4,4]nonane -# 2- (3 - acetoxyoctyl)cyclopentanone -# 1 - acetoxy- 2 - (3 - acetoxyoctyl) - cyclopent - 1 - ene -# 2- (3 - acetoxyoctyl)cyclopent - 2 - enone -# 2 - (3- acetoxyoctyl) - 3 - cyanocyclopentanone -# 3- hydroxy - 2 - (3 - hydroxyoctyl)cyclopentane carbonitrile -# 3 - (2 - tetrahydropyranyloxy) - 2- [3 - (2 - tetrahydropyranyloxy)octyl]cyclopantane carbonitrile -# 3 - (2 - tetrahydropyranyloxy) - 2- [3 - (2 - tetrahydropyranyloxy)octyl]cyclopentane carbaldehyde -# ethyl 7 - {3 - (2 - tetrahydropyranyloxy) - 2 - [3 - (2 - tetrahydropyranyloxy)- octyl]cyclopentyl}hepta - 2,4,6 - trienoate -# A. Ethyl 7 - [3 - hydroxy - 2 - (3 -