| 摘要 |
1287793 2 - Hydroxy - 3 - alkylcyclopent - 2- on-1-ones and intermediates therefor PFIZER Inc 31 Oct 1969 [10 Feb 1969 28 April 1969] 8917/71 Divided out of 1287792 Heading C2C The invention comprises compounds of the formula wherein both Xs are either Br or C1, lower alkoxy contains from 1 to 5 C atoms, and R is C 1 to C 6 alkyl, benzyl or substituted benzyl. They may be obtained by treating an alkali metal salt of 2 - carbo - (C 1 -C 5 ) - alkoxycyclopentan - 1- one with a (C 1 -C 6 ) alkyl halide or benzyl halide in the absence or presence of an alkali metal iodide and chlorinating or brominating the resulting compound by treating it with elemental Br 2 or Cl 2 , or sulphuryl chloride or bromide, The invention also comprises the preparation of compounds of the formula by hydrolysis of a compound of Formula II. Examples are given for the preparation of compounds of Formulµ I and II. The compounds of Formula I are useful as food additives. The alkali metal salt of 2-carbo-(C 1 -C 5 ) alkoxy-cyclopentan-1-one may be obtained by adding a dialkyladipate to a slurry of a base in an anhydrous inert solvent and distilling the mixture. |
