Reagent-controlled diastereoselectivity in aziridination of alkenes by chiral 3-acetoxyamino-3,4-dihydroquinazolin-4-ones: 1′-(t-butyldimethylsilyloxy)ethyl as the chiral 2-substituent on the quinazolinone
作者:Robert S. Atkinson、Michael P. Coogan、Ian S.T. Lochrie
DOI:10.1016/0040-4039(96)01055-6
日期:1996.7
Conformational preferences within the tBuMe2SiOCH(Me)CN unit in 3-acetoxyaminoquinazolinone 3 lead to well defined site preferences for H, Me and OSiMe2tBu in the transition state for, and hence high diastereoselectivity in, its reaction with β-trimethylsilylstyrene 4 to give aziridine 5.
3-乙酰氧基氨基喹唑啉酮3中的t BuMe 2 SiOCH (Me)CN单元内的构象偏爱导致H,Me和OSiMe 2 t Bu在过渡态的确定位置偏爱,因此与它的反应具有非对映选择性。 β-三甲基甲硅烷基苯乙烯4得到氮丙啶5。
A Free-Radical-Promoted Stereospecific Decarboxylative Silylation of α,β-Unsaturated Acids with Silanes
作者:Lizhi Zhang、Zhaojia Hang、Zhong-Quan Liu
DOI:10.1002/anie.201509537
日期:2016.1.4
acrylic and propiolic acids with silanes was developed. This reaction represents the first example of decarboxylative CSi bond formation and provides an efficient and convenient approach to various synthetically useful alkenyl and alkynyl organosilicon compounds through the reaction of α,β‐unsaturated acids with silanes. Spin‐trapping and EPR experiments support a radicaladdition/elimination process
adienyl iridium(III) metallacycles catalyse the hydrosilylation of alkynes using triethylsilane and no additive. The reactions proceed rapidly and efficiently at low catalyst loadings and under mild reaction conditions. If catalyses starting from terminalalkynes lead selectively to (Z)-alkenylsilanes in high yields, reactions are less efficient and selective starting from internal alkynes due to steric
Distinct Catalytic Performance of Dirhodium(II) Complexes with <i>ortho</i>-Metalated DPPP in Dehydrosilylation of Styrene Derivatives with Alkoxysilanes
provided a stable and rigid dirhodium(II) complex with ortho-metalated DPPP as the bridging ligand and the phosphonate as the axial ligand in the catalytic system. The structure of the dirhodium(II) complexes was also supported by X-raycrystal diffraction. Further experiments confirmed that the dirhodium(II) complexes may be the active species that catalyze the dehydrosilylation reaction. Control experiments