Kitagaki Shinji, Nakayoshi Tomoki, Masunaka Sota, Uchida Akane, Inano Mai, Yoshida Emika, Washino Yusuke, Aoyama Hiroshi, Yoshida Keisuke
Laboratory of Medicinal Chemistry, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, Aichi 468-8503, Japan.
Laboratory of Biophysical Chemistry, Faculty of Pharmacy, Meijo University, Nagoya, Aichi 468-8503, Japan.
Org Biomol Chem. 2024 Oct 2;22(38):7817-7833. doi: 10.1039/d4ob00831f.
A planar chiral [2.2]paracyclophane-based phosphine-phenol catalyst catalyzed the (3 + 2) annulation reaction of ethyl 2,3-butadienoate with 3-methyleneindolin-2-ones to produce 2,5-disubstituted cyclopentene-fused C3-spirooxindoles in high yields with high regio-, diastereo-, and enantioselectivities. This catalyst was suitable for reactions of not only benzylideneindolinones but also alkylideneindolinones, the chiral phosphine-catalyzed reactions of which have not yet been reported. Density functional theory calculations suggested that the formation of hydrogen bonds between the phenolic OH group of the catalyst and the allenoate carbonyl group, rather than between the OH group and the carbonyl group of indolinone, contributed to the formation of an efficient reaction space at the enantiodetermining step.
一种基于平面手性[2.2]对环芳烷的膦-酚催化剂催化了2,3-丁二烯酸乙酯与3-亚甲基吲哚-2-酮的(3 + 2)环化反应，以高收率、高区域选择性、非对映选择性和对映选择性生成2,5-二取代的环戊烯并C3-螺环氧化吲哚。该催化剂不仅适用于亚苄基吲哚酮的反应，也适用于亚烷基吲哚酮的反应，后者的手性膦催化反应尚未见报道。密度泛函理论计算表明，在对映体决定步骤中，催化剂的酚羟基与联烯酸酯羰基之间形成氢键，而非与吲哚酮羰基之间形成氢键，有助于形成有效的反应空间。
