From Highly Enantioselective Catalytic Reaction of 1,3-Diynes with Aldehydes to Facile Asymmetric Synthesis of Polycyclic Compounds
作者:Mark Turlington、Yuhao Du、Samuel G. Ostrum、Vishaka Santosh、Kathryne Wren、Tony Lin、Michal Sabat、Lin Pu
DOI:10.1021/ja204289q
日期:2011.8.3
chemoselective Pauson-Khand (PK) cycloaddition in benzaldehyde by using [Rh(cod)Cl](2) as the catalyst in the presence of rac-BINAP. High diastereoselectivity (up to >20:1) has also been achieved with the chiral dienediyne substrates containing a bulky substituent adjacent to the chiral center. In the presence of the Grubbs II catalyst, ring-closing enyne metathesis of the PK cycloaddition products led to the formation
发现 (S)-1,1'-Binaphth-2-ol (BINOL) 与 ZnEt(2)、Ti(O(i)Pr)(4) 和双环己胺结合可催化高对映选择性 (83-95 % ee) 将各种 1,3-二炔加成到不同结构的醛中。该方法提供了一种方便的途径来生成许多光学活性二烯二炔作为多环化合物的无环前体。手性二烯二炔在 rac-BINAP 存在下使用 [Rh(cod)Cl](2) 作为催化剂在苯甲醛中进行高度化学选择性的 Pauson-Khand (PK) 环加成。手性二烯二炔底物含有与手性中心相邻的大取代基,也实现了高非对映选择性(高达 >20:1)。在 Grubbs II 催化剂存在下,PK 环加成产物的闭环烯炔复分解导致形成所需的 5,5,7-和5,5,8-稠合三环化合物。5,5,7-三环化合物与马来酸酐的进一步高度非对映选择性Diels-Alder反应产生5,5,7,6-多环产物。由光学活性