Enantio- and Diastereoselective Additions to Aldehydes Using the Bifunctional Reagent 2-(Chloromethyl)-3-(tributylstannyl)propene: Application to a Synthesis of the C<sub>16</sub>−C<sub>27</sub> Segment of Bryostatin 1
作者:Gary E. Keck、Tao Yu、Mark D. McLaws
DOI:10.1021/jo048308m
日期:2005.4.1
can be accomplished without cyclization to the derived tetrahydrofuran, although this transformation is also facile. The utility of the incorporated allyl chloride functionality allows for the obvious use of such products in reactions with nucleophiles. Use of these products in a less obvious connective strategy is demonstrated in the synthesis of the C12−C27 segment of bryostatin 1 where a connective
已经研究了双官能烯丙基锡烷2-(氯甲基)-3-(三丁基锡烷基)丙烯与醛的反应。这些通常使用路易斯酸促进剂以高收率发生,并且产物可以分离和纯化而不会发生意外。使用先前描述的BITIP催化剂体系,在催化不对称烯丙基化(CAA反应)中也实现了高收率和高对映选择性。游离羟基的保护可在不环化成衍生的四氢呋喃的情况下完成,尽管这种转化也很容易。掺入的烯丙基氯官能度的实用性允许在与亲核试剂反应中明显使用此类产物。C 12 -C的合成证明了这些产物在不太明显的结缔策略中的使用bryostatin 1的27个片段,其中采用了结缔或“ lynchpin”双烯丙基化过程。从醛的初始螯合控制的烯丙基化得到的β型羟基烯丙基氯16转化为allylstannane 19和在第二反应烯丙基施加,从而允许苔藓抑素C环骨架的以立体选择性的方式高度会聚合成。