(+)-2, readily obtained from (−)-α-pinene 1 was elaborated to (+)-3 in an attempt to construct the AB rings of taxoids employing the ring-closure metathesis (RCM) reaction as the key step. In the event, a novel ring-opening/ring-closing metathesis reaction was encountered in the relatively strain free cyclohexenyl ring of (+)-3.
尝试从(-)-α-pine烯1轻松获得的
环己烯酮(+)- 2修饰为(+)- 3,以利用闭环复分解(RCM)反应构建关键类
紫杉醇的AB环步。在这种情况下,在(+)- 3的相对无应变的
环己烯基环中遇到了新的开环/闭环复分解反应。