IMPROVED SYNTHESIS OF 2-(4-(4-CHLOROPHENYL) CYCLOHEX-1-ENYL) -3, 4-DIHYDRONAPHTHALEN-1 (2H)-ONE; AN INTERMEDIATE FOR ATOVAQUONE

摘要

A process for preparation of 2-(4-(4-chlorophenyl) cyclohex-l-enyl)-3,4-dihydronaphthalen- 1(2H)-one (V), key intermediate for synthesis of Atovaquone [I]. The process for preparation of compound(V) comprising of the steps of; i) Reaction of 2-(4-(4-chlorophenyl)-1-hydroxycyclohexyl)-3,4-dihydronaphthalen- 1(2H)-one (IV) with trifluro acetic anhydride in presence of base in organic solvent to yield compound of formula (XIa) ii) Elimination of trifluoroacetyl functionality of compound (XIa) in organic solvent and in presence of organic base to give compound of formula (V). The invention also provides a Process for preparation of compound(XIa) comprising of the steps of; i) reaction of 2-(4-(4-chlorophenyl)-l-hydroxy cyclohexyl)-3,4-dihydronaphthalen- 1(2H)-one (IV) with trifluro acetic anhydride in presence of organic base in organic solvent. A further process is provided for preparation of compound(V) from compound (XIa) comprising elimination reaction of trifluoroacetyl functionality compound (XIa) in organic solvent and in presence of organic base.