Direct Synthesis of Alkenylboronates from Alkenes and Pinacol Diboron via Copper Catalysis
作者:Wenkui Lu、Zengming Shen
DOI:10.1021/acs.orglett.8b03599
日期:2019.1.4
We report an efficient approach for the direct synthesis of alkenylboronates using copper catalysis. The Cu/TEMPO catalyst system (where TEMPO = (2,2,6,6-tetramethylpiperidin-1-yl)oxyl) exhibits both excellent reactivity and selectivity for the synthesis of alkenylboronates, starting from inexpensive and abundant alkenes and pinacol diboron. This approach allows for the direct functionalization of
Enantioselective Construction of Quaternary Stereogenic Centers by the Addition of an Acyl Anion Equivalent to 1,3-Dienes
作者:Nathan J. Adamson、Sangjune Park、Pengfei Zhou、Andrew L. Nguyen、Steven J. Malcolmson
DOI:10.1021/acs.orglett.0c00412
日期:2020.3.6
We report the enantioselective formation of quaternary stereogenic centers by the intermolecular addition of malononitrile, an acyl anion equivalent, and related pronucleophiles to several 1,3-disubstituted acyclic 1,3-dienes in the presence of a Pd-PHOX catalyst. Products are obtained in up to 88% yield and 99:1 er and in most cases are formed as a single regioisomer. The products' malononitrile unit
(<i>Z</i>)-Selective Hydroboration of Terminal Alkynes Catalyzed by a PSP–Pincer Rhodium Complex
作者:Yanzong Lyu、Naoyuki Toriumi、Nobuharu Iwasawa
DOI:10.1021/acs.orglett.1c03606
日期:2021.12.3
A highly (Z)-selective hydroboration of terminal alkynes was achieved using a thioxanthene-based PSP–pincer rhodium catalyst. This hydroboration exhibited good chemoselectivity toward alkynes over carbonyl compounds such as ketones and aldehydes. The mechanistic studies indicated the involvement of rhodium–vinylidene intermediates, and the high (Z)-selectivity could be attributed to the rigid and electron-rich
使用基于噻吨的 PSP-钳形铑催化剂实现了末端炔烃的高 ( Z ) 选择性硼氢化反应。与羰基化合物(如酮和醛)相比,这种硼氢化反应对炔烃表现出良好的化学选择性。机理研究表明铑-亚乙烯基中间体的参与,高(Z)选择性可归因于 PSP-铑催化剂的刚性和富电子性质。
Diastereo‐ and Enantioselective 1,4‐Difunctionalization of Borylenynes by Catalytic Conjunctive Cross‐Coupling
作者:Chunyin Law、Elton Kativhu、Johnny Wang、James P. Morken
DOI:10.1002/anie.202001580
日期:2020.6.22
Enantioselective conjunctive cross‐coupling of enyne‐derived boronate complexes occurs with 1,4 addition of the electrophile and migrating group across the π system. This reaction pathway furnishes α‐boryl allenes as the reaction product. In the presence of a chiral catalyst, both the central and axial chirality of the product can be controlled during product formation.