Patent ID: 11952335
Assignee: FIRMENICH SA
Field: Organic fine chemistry (Chemistry)
Classification: CPC C | IPC C

Claim 0:
1. A process for the preparation of a compound of formula, in the form of any one of its stereoisomers or a mixture thereof, and wherein n is an integer between 0 and 2, each R1, independently from each other, represents a substituent of the aromatic ring and is a C1-6 alkyl group, a C2-6 alkenyl group or a C1-6 alkoxy group; R2 represents a C1-3 alkyl group; and R3 represents a hydrogen atom, a C1-6 alkyl group or a C2-6 alkenyl group;
comprising the cyclisation of a compound of the formula (II), in the form of any one of its stereoisomers or a mixture thereof, and wherein n, R1, R2 and R3 have the same meaning as defined in formula (I); and
A represents a C(O)OC(O)R4 group, a C(O)Cl group or a COOH group wherein R4 represents a C1-6 alkyl group substituted by one or more chlorine or fluorine atoms;
in a presence of a Friedel-Crafts acylation reagent.