Patent GB-1365173-A (GB)
Title: Cyclopentane derivatives
IPC: C07D307/935
Filed: 1972-02-04
Abstract: 1365173 2-Hydroxycyclopentaneacetic acid γ-lactones IMPERIAL CHEMICAL INDUSTRIES Ltd 10 Jan 1973 [4 Feb 1972] 5353/72 Heading C2C [Also in Division C3] The invention comprises 2-hydroxycyclopentaneacetic acid γ-lactones of the Formula XXIII: whereinX is ethylene or trans-vinylene; Z is Cl, Br or I; and R<SP>3</SP> is C 1-10  alkyl, C 4-10  alkenyl, -A<SP>1</SP>.O.R<SP>4</SP>, -A<SP>2</SP>.R<SP>5</SP> or -A<SP>3</SP>.A<SP>4</SP>.R<SP>6</SP>, wherein A<SP>1</SP> is C 1-9  alkylene or C 5-7  cycloalkyl, provided that A<SP>1</SP> and R<SP>4</SP> together contain not more than 10 carbon atoms; A<SP>2</SP> is C 2-3  alkylene, optionally bearing 1 or 2 C 1-4  alkyl substituents, R<SP>5</SP> is aryl optionally substituted by halogen, NO 2 , C 1-3  alkyl, C 1-3  alkoxy, C 1-3  haloalkyl or di-(C 1-3  alkyl) amino; A<SP>3</SP> is C 1-3  alkylene optionally bearing 1 or 2 C 1-3  alkyl substituents, A<SP>4</SP> is O, S, SO or C 1-4  alkylimino; and R<SP>6</SP> is aryl, benzyl or furfuryl optionally substituted by halogen C 1-4  alkyl, C 2-4  alkenyl; C 1-4  haloalkyl, C 1-4  alkoxy, C 2-4  alkenyloxy, C 1-4  acylamino or di-(C 1-3  alkyl) amino and their conversion by hydrogenolysis to 2-hydroxycyclopentaneacetic γ-lactones of the above formula in which Z is a hydrogen atom. The novel γ-lactones of the above formula are obtained by reacting cyclopenteneacetic acids of the formula with aqueous chlorinating, brominating or iodinating agents. The following intermediates and starting materials are prepared:- [4α - Hydroxy - 5# - (3 - hydroxydec - trans - 1- enyl) - 2 - cyclopenten - 1α - yl] acetic acid, its sodium salt and #-lactone, 7-syn-(3-hydroxydectrans - 1 - enyl) bicyclo[2.2.1]hept - 2 - en - 5 - one and its acetate, 5-chloro-5-cyano - 7 - syn - (3-oxodec - trans - 1 - enyl) bicyclo[2.2.1] hept - 2 - ene, 5 - chloro - 5 - cyano - 7 - syn - (3 - hydroxydectrans - 1 - enyl) bicyclo[2.2.1]hept- 2 - ene, 5- chloro - 5 - cyano - 7 - syn - (3 - oxo oct - trans - 1- enyl) bicyclo[2.2.1]hept - 2 - ene, 5 - chloro - 5- cyano - 7 - syn - (3 - hydroxyoct - trans - 1 - enyl)- bicyclo[2.2.1]hept - 2 - ene, 7 - syn - (3 - hydroxyoct - trans - 1 - enyl) bicyclo[2.2.1]hept - 2 - en - 5- one, sodium [4a - hydroxy - 5# - (3 - hydroxyocttrans - 1 - enyl) cyclopent - 2 - en - 1α - yl) acetate 5 - chloro - 5 - cyano - 7 - syn - (4 - methyl - 3 - oxo- 5 - phenylpent - trans - 1 - enyl) bicyclo[2.2.1]- hept - 2 - ene, 5 - chloro - 5 - cyano - 7 - syn - (3- hydroxy - 4 - methyl - 5 - phenyl - pent - trans - 1- enyl) bicyclohept - 2 - ene, 7 - syn - (3 - hydroxy- 4 - methyl - 5 - phenylpent - trans - 1 - enyl) bicyclo[2.2.1]hept - 2 - en - 5 - one, sodium [4α- hydroxy - 5# - (3 - hydroxy - 4 - methyl - 5 - phenylpent - trans - 1 - enyl) - 2 - cyclopenten - 1α - yl]- acetate, 5 - chloro - 5 - cyano - 7 - syn - (4 - pchlorophenoxy - 3 - oxobut - trans - 1 - enyl) - bicyclo[2.2.1]hept - 2 - ene, 5 - chloro - 5 - cyano - 7- syn - (3 - hydroxy - 4 - p - chlorophenoxy buttrans - 1 - en - yl) bicyclo[2.2.1]hept - 2 - ene, 7- syn - (3 - hydroxy - 4 - p - chlorophenoxybuttrans - 1 - enyl) bicyclo[2.2.1]hept - 2 - en - 5 - one and sodium [4α - hydroxy - 5# - (3 - hydroxy - 4- p - chlorophenoxybut - trans - 1 - enyl) - 2 - cyclopenten-1α-yl) acetate.