Excellent Chiral Introduction by Diene Iron-Tricarbonyl Moiety. II: A Formal Synthesis of (+)- and (-)-Frontalin Using a Diastereoselective 1,2-Nucleophilic Addition of Organometallics into a (Z)-Dienone Fe(CO)3 Complex.
作者:Yoshiji TAKEMOTO、Jun TAKEUCHI、Ken-ichiro MORIO、Takahisa NAKAMOTO、Chuzo IWATA
DOI:10.1248/cpb.44.940
日期:——
A nucleophilic addition of alkyllithiums to the (Z)-dienone iron-tricarbonyl [Fe(CO)3] complex (3) gave the (Z)-dienol complex (4) exclusively, while the reaction of 3 with alkylmagnesium bromide or trialkylaluminum provided the (E)-dienol complex (2) via the isomerization of 3 to the (E)-dienone complex (1). Application of this methodology was demonstrated in a formal synthesis of both (+)- and (-)-frontalin from the same chiral starting material, (2S, 5S)-(2E, 4Z)-tricarbonyl[2-5-η-11-chloro-2, 4-undecadien-6-one]iron} (8).
将烷基锂的亲核加成反应与(Z)-二烯酮铁三羰基 [Fe(CO)3] 复合物 (3) 反应,专门得到(Z)-二烯醇复合物 (4),而与烷基镁溴化物或三烷基铝的反应则通过 (3) 的异构化生成(E)-二烯酮复合物 (1),从而提供了(E)-二烯醇复合物 (2)。这一方法在从相同手性起始材料 (2S, 5S)-(2E, 4Z)-三羰基[2-5-η-11-氯-2, 4-十一烯-6-酮]铁} (8) 的正式合成 (+)- 和 (-)-frontalin 中得到了应用。