Air-Stable Solid Aryl and Heteroaryl Organozinc Pivalates: Syntheses and Applications in Organic Synthesis
作者:Sophia M. Manolikakes、Mario Ellwart、Christos I. Stathakis、Paul Knochel
DOI:10.1002/chem.201403015
日期:2014.9.15
air‐stable, solid, polyfunctional aryl and heteroarylzinc pivalates were efficiently prepared by either magnesium insertion or Hal/Mg exchange followed by transmetalation with Zn(OPiv)2 (OPiv=pivalate). By reducing the amount of LiCl the air stability could be significantly enhanced compared with previously prepared reagents. An alternative route is directed magnesiation using TMPMgCl⋅LiCl (TMP=2,2,6,6‐
通过插入镁或Hal / Mg交换,然后用Zn(OPiv)2(OPiv =新戊酸酯)进行金属转移,可以有效地制备各种空气稳定的固体多官能芳基和杂芳基锌新戊酸酯。与以前制备的试剂相比,通过减少LiCl的含量,可以显着提高空气稳定性。的替代路线是使用TMPMgCl涉及镁化⋅的LiCl(TMP = 2,2,6,6-四甲基),然后用锌(OPiv)转移金属化2,或者对于非常敏感的底物,直接浸锌通过使用TMPZnOPiv。这些锌试剂不仅对空气具有极好的稳定性,而且它们的C范围也很广。C键形成反应,例如烯丙基化和碳环化反应,以及醛的加成和1,4加成反应。可以通过使用过量的TMSC1来克服无所不在的新戊酸酯阴离子的副反应来进行酰化反应。