Abstract: In CH, CN and other coordinating solvents, the tungsten-carbene complexes (CO) 5W= C (OCH2CH2CH= CHOCH3) C, H4-p-CH3 (trans-and cis-5) are stereospecifically converted to the cyclopropanes 1-(4-methylphenyl)-2-oxa-6-methoxybicyclo [3.1. O] hexane (exo-and endo-8) in> 95% yield. This cyclopropanation follows clean first-order kinetics in CH3CN (k=(2.64 f 0.08) X s-'at 42" C for trans-5). This reaction is proposed to proceed via ...
