High‐Throughput Ligand Screening Enables the Enantioselective Conjugate Borylation of Cyclobutenones to Access Synthetically Versatile Tertiary Cyclobutylboronates
作者:Helen A. Clement、Michele Boghi、Rory M. McDonald、Louise Bernier、Jotham W. Coe、William Farrell、Christopher J. Helal、Matthew R. Reese、Neal W. Sach、Jack C. Lee、Dennis G. Hall
DOI:10.1002/anie.201909308
日期:2019.12.16
enantioselectivity and diastereoselectivity. Vital to this advance are the development of a novel approach to α,β unsymmetrically disubstituted cyclobutenone substrates and the use of a high-throughput chiral ligand screening platform. The synthetic utility of both the boronic ester and ketone functionalities is displayed, with remarkable chemoselectivity for either group being possible in this small ring scaffold
Nickel(0)-catalyzed synthesis of substituted phenols from cyclobutenones and alkynes
作者:Mark A. Huffman、Lanny S. Liebeskind
DOI:10.1021/ja00007a072
日期:1991.3
The results above show that the convergent synthesis of substituted phenols is possible by nickel(0)-catalyzed ring opening and cycloaddition of cyclobutenones with alkynes. Future efforts will explore application of this method to intramolecular reactions
Cyclobutenones have been explored as a new type of chiral 1,4‐dipole four‐carbon synthon, which readily undergoes organophosphine‐mediated CC bond cleavage and asymmetric intermolecular 1,4‐dipolar spiroannulation with isatylidenemalononitrile in the presence of aminoacid‐derived chiral phosphine catalyst to furnish enantioenriched 3‐spirocyclohexenone 2‐oxindoles in good yield with up to 87 % ee
A Nickel‐Catalyzed Benzannulation Approach to Aromatic Boronic Esters
作者:Anne‐Laure Auvinet、Joseph P. A. Harrity
DOI:10.1002/anie.201007598
日期:2011.3.14
Off and on: A nickel‐catalyzedbenzannulation of alkynylboronates provides functionalized phenols with high levels of chemo‐ and regioselectively. While transmetalation of organoboron intermediate to organonickel does not occur during cycloaddition, it is “switched on” by addition of base, thus allowing a one‐pot benzannulation and cross‐coupling to be realized (see scheme; Pin=pinacolato, Ms=mesyl)