In the presence of a catalytic amount of Au(I) and Ag(I) salts, the 14-membered furanophane II with an allene function located across the ring undergoes both a transannular [4+3] and [4+2] cycloaddition. Secondary rearrangement products containing a tricyclic ring system were isolated when the catalyst was PtCl2.
作者:Benjaminâ W. Gung、Derekâ T. Craft、Laurenâ N. Bailey、Kristin Kirschbaum
DOI:10.1002/chem.200902185
日期:2010.1.11
using a CrCl2‐promoted reaction. In the presence of either a AuI or AuIII catalyst, a tandem 3,3‐rearrangement/transannular [4+3] cycloaddition reaction occurred to give propargyl acetates that are regio‐ and diastereospecific. The regiochemistry of the product is controlled by the position of the acetoxy group in the starting material and the stereochemistry of the reaction depends on the ring size
通过使用 CrCl 2促进的反应制备了含有呋喃环的大环乙酸炔丙酯。在 Au I或 Au III催化剂存在下,发生串联的 3,3-重排/跨环 [4+3] 环加成反应,得到具有区域和非对映特异性的乙酸炔丙酯。产物的区域化学受起始材料中乙酰氧基的位置控制,反应的立体化学取决于环的大小。
The first transannular [4+3] cycloaddition reaction: synthesis of the ABCD ring structure of cortistatins
作者:Derek T. Craft、Benjamin W. Gung
DOI:10.1016/j.tetlet.2008.07.155
日期:2008.10
allene and a furan strategically located at across the ring from each other is synthesized using an allene ring closing metathesis reaction. Upon treatment of the macrocycle with a catalytic amount of Pd(OAc)(2) and other additives, the first transannular [4+3] cycloaddition occurred to yield 37% of a tetracyclic compound containing the ABC ring structure of the natural products cortistatins.