Regio‐ and Stereoselective Homologation of 1,2‐Bis(Boronic Esters): Stereocontrolled Synthesis of 1,3‐Diols and Sch 725674
作者:Alexander Fawcett、Dominik Nitsch、Muhammad Ali、Joseph M. Bateman、Eddie L. Myers、Varinder K. Aggarwal
DOI:10.1002/anie.201608406
日期:2016.11.14
1,2-Bis(boronic esters), derived from the enantioselective diboration of terminal alkenes, can be selectively homologated at the primary boronic ester by using enantioenriched primary/secondary lithiated carbamates or benzoates to give 1,3-bis(boronic esters), which can be subsequently oxidized to the corresponding secondary-secondary and secondary-tertiary 1,3-diols with full stereocontrol. The transformation
Construction of Multiple, Contiguous Quaternary Stereocenters in Acyclic Molecules by Lithiation-Borylation
作者:Charlotte G. Watson、Angelica Balanta、Tim G. Elford、Stéphanie Essafi、Jeremy N. Harvey、Varinder K. Aggarwal
DOI:10.1021/ja509029h
日期:2014.12.17
construction of two quaternary centers, this methodology fails. Instead, using mixed boranes (tBuBMe2), the synthesis of adjacent quaternary stereogeniccenters with full stereocontrol was successful. The process can be repeated two or three times in onepot leading to carbon chains bearing multiple contiguous quaternary stereogeniccenters. The boranes were converted into tertiary alcohols or C-tertiary amines
氨基甲酸酯锂化和硼酸化为硼试剂的同系化提供了一种强有力的方法。然而,当应用于受阻系统(带有 tBu-硼酸酯的二级氨基甲酸酯)以构建两个四元中心时,这种方法失败了。相反,使用混合硼烷 (tBuBMe2),具有完全立体控制的相邻四元立体中心的合成是成功的。该过程可以在一锅中重复两到三次,从而产生带有多个连续四元立体中心的碳链。使用氯胺将硼烷转化为叔醇或 C-叔胺。通过计算确定烷基对 Me 基团迁移的高选择性的起源。
Transition-metal-free synthesis of 1,1-diboronate esters with a fully substituted benzylic center via diborylation of lithiated carbamates
作者:Haonan Zhao、Min Tong、Haijun Wang、Senmiao Xu
DOI:10.1039/c7ob00654c
日期:——
lithiation-borylation method has been developed to access a variety of 1,1-diboronate esters with a fully substituted benzylic center from readily available secondary benzylic N,N-diisopropyl carbamates. The method is applicable to scale-up synthesis of 1,1-diboron compounds. Furthermore, the current method is also applicable to synthesizing opticallyactive 1,1-silylboronate esters.
作者:Molly E. Fairchild、Adam Noble、Varinder K. Aggarwal
DOI:10.1002/anie.202205816
日期:2022.8.26
2-metallate rearrangement of 6-membered cyclic alkenyl boronate complexes enables the synthesis of cyclopentyl boronic esters bearing two contiguous, fully substituted stereocenters with excellent levels of enantio- and diastereocontrol. The utility of our methodology is demonstrated in the asymmetric totalsynthesis of (+)-herbertene-1,14-diol.