Ring opening reactions of thirrans by alkoxo- and aryloxo-gold(I) complexes

摘要

Alkoxo- and aryloxo-gold(I) complexes [Au(OR)L][R = CH(CF_3)_2, L = PPh_3, 1a or PCy_3, 1b; R = Rh, L = PPh_3 1c, PCy_3 1d or PMe_3 1e] smoothyl reacted with ethylene sulfide to give the corresponding 2-(alkoxy- or -aryloxy) ehtyl-sulfanylgold(I) complexes [Au(SCH_2CH_2OR)L]2 at room temperature. Similar treatments of 1a-1e with propylene sulfide, isobutylene sulfide, or styrene sulfide selectively cleaved the less hindered C-S bond of thiiranes to give corresponding 2-(alkoxy- or -aryloxy)ethylsulfanylgold(I) complexes. Reactions of 1a with cis- and trans-2-butene sulfide gave syn- and anti-[Au(SCHMeCHMeOR)L], respectively, suggesting a mechanism involving an S_N2 type trans addition of alkoxogold(I) complexes toward thiiranes.