Stereocontrolled synthesis of carbon-carbon double bond locked analogues of strobilurins which are characterized by a trans-1,2-disubstituted cyclopropane ring

The racemic forms of four new carbon-carbon double bond locked analogues of strobilurins, which are characterized by a trans-1,2-disubstituted cyclopr opane ring, have been synthesized according to a strategy which involves pa lladium-catalyzed cross-coupling reactions between methyl (Z)-2-iodo-3-meth oxypropenoate and organometallic derivatives such as (1R*,2R*)-2-phenylcycl opropylboronic acid and (1R*,2R)-1-(2-bromozinciophenyl)-2-arylcyclopropane s. Tnt: boronic acid has been prepared via cyclopropanation of (E)-2-phenyl ethenyl-1,3,2-dioxaborinane and the organozinc compounds have been synthesi zed from easily available (E)-2-bromostilbenes. (C) 2001 Elsevier Science L td. All rights reserved.