Treatment of the gold 3-methoxy-3-phenylpropyl complex (P)AuCH₂CH₂CH(OMe)Ph [P = P(t-Bu)₂o-biphenyl] with AlCl₃ at −78 °C led to the immediate (≤5 min) formation of a 4:1 mixture of phenylcyclopropane and (1-methoxypropyl)benzene in 86 ± 5% combined yield. Lewis acid activation of the stereochemically pure isotopomer erythro-(P)AuCH₂CHDCH(OMe)Ph led to the formation of cis-2-deuterio-1-phenylcyclopropane in 84 ± 5% yield as a single stereoisomer, which established that cyclopropanation occurred with inversion of the γ-stereocenter. Similarly, ionization of the stereochemically pure cyclohexyl gold complex cis-(P)AuCHCH₂CH(OMe)CH₂CH₂CH₂ at −78 °C formed bicyclo[3.1.0]hexane in 82% ± 5% yield, which validated a low energy pathway for cyclopropanation involving inversion of the α-stereocenter. Taken together, these observations are consistent with a mechanism for cyclopropane formation involving backside displacement of both the Cγ leaving group and the Cα (L)Au⁺ fragment via a W-shaped transition state.

中文翻译：

---

通过路易斯酸活化（γ-甲氧基）烷基金（I）配合物形成环丙烷

在−78°C下用AlCl ₃处理3-甲氧基-3-苯基丙基金（P）AuCH ₂ CH ₂ CH（OMe）Ph [ P = P（t -Bu）₂ o-联苯]金导致立即（≤5分钟）形成苯基环丙烷和（1-甲氧基丙基）苯的4：1混合物，合并产率为86±5％。立体化学纯的异构体赤型-（P）AuCH ₂ CHDCH（OMe）Ph的路易斯酸活化导致顺式形成-2-氘代-1-苯基环丙烷为单一立体异构体，产率为84±5％，这表明环丙烷化是随着γ-立体中心的反转而发生的。同样，立体化学纯的环己基金配合物顺式-（P）Au CHCH ₂ CH（OMe）CH ₂ CH ₂ CH ₂在-78°C下电离形成双环[3.1.0]己烷，产率为82％±5％，验证了涉及α-立体中心反转的环丙烷化低能途径。综上所述，这些观察结果与环丙烷形成机理一致，该机理涉及Cγ离去基团和Cα（L）Au ⁺片段通过W形过渡态向后位移。