β‐Diazocarbonyl Compounds: Synthesis and their Rh(II)‐Catalyzed 1,3 C−H Insertions
作者:Liyin Jiang、Zhaofeng Wang、Melanie Armstrong、Marcos G. Suero
DOI:10.1002/anie.202015077
日期:2021.3.8
of ketone silyl enol ethers with diazomethyl‐substituted hypervalent iodine reagents that gives access to unusual β‐diazocarbonyl compounds. The potential of this unexplored class of diazo compounds for the development of new reactions was demonstrated by the discovery of a rare Rh‐catalyzed intramolecular 1,3 C−H carbene insertion that led to complex cyclopropanes with excellent stereocontrol.
A General Method for the Enantioselective Synthesis of Pantolactone Derivatives
作者:David A. Evans、Jimmy Wu、Craig E. Masse、David W. C. MacMillan
DOI:10.1021/ol026489d
日期:2002.10.1
An efficient enantioselective synthesis of beta,beta-dialkyl-gamma-substituted pantolactones has been achieved utilizing the cationic [Sc((S,S)-R-pybox)](Cl)(2)(+), R = Ph (9), t-Bu (10), complex in a catalyzed aldol reaction as the key step. The pantolactone derivatives are isolated in high enantiomeric excesses. [reaction: see text]
Synthesis of Allylboronates via Zweifel‐type Deprotonative Olefination
作者:Nuo Xu、Jianeng Xu、Qing Zhu、Chao Liu
DOI:10.1002/adsc.202001351
日期:2021.4.27
allylboronates via Zweifel‐type deprotonative olefination was demonstrated. Tetrasubstituted vinylboronates were used as the substrates. NCS (N‐chlorosuccinimide) was used as a bifunctional additive, electrophile and base. This method exhibited a different elimination strategy in Zweifel type transformation to afford allylboronates. The homo‐alcohols and alkenes were stereoselective synthesized from the obtained
On the Origin of Rh-Catalyzed Selective Ring-Opening Amidation of Substituted Cyclopropanols to Access β<sup>2</sup>-Amino Ketones
作者:Minhan Lee、Joon Heo、Dongwook Kim、Sukbok Chang
DOI:10.1021/jacs.1c12934
日期:2022.3.2
place in the development of new pharmaceuticals and peptidomimetics. Herein, we report a highly efficient Rh-catalyzed ring-opening amidation of substituted cyclopropanols, which turned out to serve as a linchpin for the selective synthesis of β2-amino ketones to outcompete the formation of β3-isomers. Instead of the generally accepted rationale to consider steric factors for the β2-selectivity, orbital