Cobalt‐Catalyzed Transfer Hydrogenation of α‐Ketoesters and
<i>N</i>
‐Cyclicsulfonylimides Using H
<sub>2</sub>
O as Hydrogen Source
作者:Yang Gao、Xuexin Zhang、Ronibala Devi Laishram、Jingchao Chen、Kangkui Li、Keyang Zhang、Guangzhi Zeng、Baomin Fan
DOI:10.1002/adsc.201900636
日期:2019.9.3
A Co‐catalyzed effective transferhydrogenation of various α‐ketoesters and N‐cyclicsulfonylimides by safe and environmentally benign H2O as hydrogensource is described. The reaction used easily available and easy to handle zinc metal as a reductant. Interestingly, the catalytic system does not require ligand for reduction of N‐cyclicsulfonylimides.
A highly efficient photocatalyticaerobicoxidation of cyclic sulfamides to synthesize cyclic N-sulfonyl imines with Ir(ppy)2(dtbpy)PF6 as photocatalyst is reported. These environmentally friendly transformations exihibit good to excellent isolated yields and good generality with respect to both five-membered and six-membered cyclic sulfamides.
H8‐BINOL‐Derived Chiral η6‐Benzene Ligands: New Opportunities for the Ruthenium‐Catalyzed Asymmetric C−H Activation
作者:Junxuan Li、Guodong Wang、Weicong Guo、Jijun Jiang、Jun Wang
DOI:10.1002/anie.202405782
日期:2024.7.29
A class of (S)-H8-BINOL-derived chiral η6-benzene ligands has been developed, which can coordinate with ruthenium(II) highly site-selectively.The related chiralruthenium(II) catalysts proved highly effective for the asymmetric C−H activation of N-sulfonyl ketimines with alkynes, affording a series of chiral spirocyclic sultams in up to 99 % yield with up to >99 % ee.
Iodotrimethylsilane and Catalytic Iodine Promoted Cyclization for the Facile Synthesis of 3-Monoarylated Five-Membered Benzosultams
作者:Zhao-Peng Liu、Yue-Hui Dong、Qiong-Wei Ni、Shu-Tao Ma
DOI:10.3987/com-09-11884
日期:——
3-Monoarylated five-membered benzosultams with various functional groups were prepared by simple and convenient two-step procedures. N-t-Bu-benzenesulfonamides were lithiated and reacted with substituted aromatic aldehydes to form the corresponding carbinols, which were converted to the cyclic compounds via a sequence of consecutive processes mediated by TMSCl-NaI-MeCN reagent and catalytic amount of iodine. Iodine played a crucial role in the eliminating the reductive side reaction in the cyclization processes.