Synthesis of Angular Triquinanes from 1-Alkynylbicyclo[3.2.0]hept-2-en-7-ones. A Tandem Alkoxy-Cope Ring Expansion/Transannular Ring Closure Reaction
作者:Sharad K. Verma、Everly B. Fleischer、Harold W. Moore
DOI:10.1021/jo0009503
日期:2000.12.1
rearrangement which proceeds by way of a strained cyclic allene intermediates (e.g.,17). This leads to the formation of angularly fused triquinanes (e.g., 20) in which each of the rings is functionally differentiated. Bicyclo[6.3. 0]undecadienones (e.g., 36) are the major products when the reactions are quenched with aqueous bicarbonate rather than TBAF. Under analogous conditions 2-alkylidene-1-alkynylbicyclo[3
将乙烯基锂试剂加到二烷基方酸衍生的1-炔基双环[3.2.0]庚-2-烯-7-酮(15)的羰基上,然后进行TBAF处理,得到低温阴离子加速的烷氧基-应付通过重排的环状Allene中间体(例如17)进行的重排。这导致形成角稠合的三喹烷(例如20个),其中每个环在功能上是不同的。双环[6.3。0]十一碳二烯酮(例如36)是将反应用碳酸氢盐水溶液而不是TBAF淬灭的主要产物。在类似条件下2-亚烷基-1-炔基双环[3.2。0]庚-7-酮还通过一种机制建立双环[6.3.0]十一碳二烯酮,该机制已建立,涉及在紧张的丙二烯中间体中发生1,5-氢转移。