An enantioselectivesynthesis of α-fluoroaryl homoallylic amines in 52–71% yields and 76–93% enantioselectivities has been achieved via the allylboration of the corresponding fluorinated N-aluminobenzaldimines with B-allyldiisopinocampheylborane in the presence of methanol, followed by alkaline hydrogen peroxide workup. Crotylboration of these aluminobenzaldimines with potassium B-methoxy B-E- or
Enantio- and diastereoselective synthesis of β-substituted-δ-aminoboronic esters from nitriles
作者:P. Veeraraghavan Ramachandran、Wataru Mitsuhashi、Debanjan Biswas、Daniel R. Nicponski
DOI:10.1016/j.tetlet.2013.06.076
日期:2013.9
The first stereocontrolled synthesis of the title δ-aminoboronic esters—proceeding from commercially available nitriles—via a reduction, Brown’s ‘allyl’ boration reaction, a Boc-protection, a hydroboration, an oxidative elimination of α-pinene, and an esterification reaction, has been reported in excellent enantio- and diastereoselectivities.
New Generation of Highly Reactive Allylborating Agents For Cu(I)-Catalyzed Allylation of Chiral Sulfinylimines
作者:Michael S. Alexeev、Tatyana V. Strelkova、Michail M. Ilyin, Jr.、Yulia V. Nelyubina、Ivan A. Bespalov、Michael Medvedev、Victor N Khrustalev、Nikolai Kuznetsov
DOI:10.1039/d4ob00291a
日期:——
active reagents is an attractive strategy that meets the modern principles of sustainable development of chemistry. In the current study, we for the first time describe the method and general principles of Cu(I)-catalyzed allylation of imines with amine adducts of allylic triorganoboranes. Triallylborane is an extremely reactive compound and cannot be used for the catalytic allylation of imines, whereas
使用高活性试剂实施选择性催化过程是一种有吸引力的策略,符合化学可持续发展的现代原则。在本研究中,我们首次描述了Cu( I )催化亚胺与烯丙基三有机硼烷胺加合物的烯丙基化反应的方法和一般原理。三烯丙基硼烷是一种极其活泼的化合物,不能用于亚胺的催化烯丙基化,而其胺加合物是理想的催化底物。胺片段的结构成功地平衡了烯丙基硼试剂的安全性、选择性和稳定性,使其在催化烯丙基化反应中表现出高活性,超过任何已知的烯丙基硼烷许多倍。获得的结果得到定量动力学数据和 DFT 计算的支持。该系统的催化功效在亚磺酰亚胺模型(23 个例子)上得到了证明。实现了高达 >99% 的高非对映选择性,包括克级合成 2-羟基苯基衍生物。考虑到三烯基硼烷(AAT)的胺加合物的高反应活性和无与伦比的原子经济性,它们可以被认为是Cu( I )和其他合适金属催化剂的潜在烯丙基化试剂。