available ketones. Mechanistic studies suggest that this Rh-catalyzed deoxygenative borylation of ketones goes through an alkene intermediate, which undergoes regiodivergent hydroboration to afford linear and branched alkylboronates. The different steric effects of PPh2Me and P(nBu)3 were found to be responsible for product selectivity by density functional theory calculations. The alkene intermediate
在这里,我们报告了一种有效的铑催化酮脱氧硼酸化合成烷基硼酸酯,其中区域选择性可以通过选择配体来切换。直链烷基硼酸酯仅在 P( n Bu) 3存在下获得,PPh 2 Me 有利于支链烷基硼酸酯的形成。该协议还允许从现成的酮中获取 1,1,2-三硼酸酯。机理研究表明,这种 Rh 催化的酮类脱氧硼酸化反应经过烯烃中间体,该中间体经历区域发散硼氢化反应,得到直链和支链烷基硼酸酯。PPh 2 Me 和 P( n Bu) 3的不同空间位阻效应通过密度泛函理论计算发现是产物选择性的原因。烯烃中间体也可以依次进行脱氢硼酸化和硼氢化反应以提供三硼酸酯。
[EN] FUSED HETEROCYCLIC COMPOUNDS AS S1P MODULATORS<br/>[FR] COMPOSÉS HÉTÉROCYCLIQUES CONDENSÉS À TITRE DE MODULATEURS DE S1P
申请人:ABBVIE INC
公开号:WO2017036978A1
公开(公告)日:2017-03-09
The invention relates to heterocyclic compounds as S1P modulators, pharmaceutical compositions comprising such compounds, and uses thereof in the treatment, alleviation or prevention of diseases or disorders mediated by an S1P receptor.
FeCl<sub>2</sub>-catalyzed hydroboration of aryl alkenes with bis(pinacolato)diboron
作者:Yang Liu、Yuhan Zhou、Huan Wang、Jingping Qu
DOI:10.1039/c5ra14869c
日期:——
Alkylboronates were synthesized by a ligand-free ferrous chloride catalyzed anti-Markovnikov hydroboration of un-activated aryl alkenes with bis(pinacolato)diboron.
Unlocking the catalytic potential of tris(3,4,5-trifluorophenyl)borane with microwave irradiation
作者:Jamie L. Carden、Lukas J. Gierlichs、Duncan F. Wass、Duncan L. Browne、Rebecca L. Melen
DOI:10.1039/c8cc09459d
日期:——
The catalytic activity of tris(3,4,5-trifluorophenyl)borane has been explored in the 1,2-hydroboration reactions of unsaturated substrates. Under conventional conditions, the borane was found to be active only in the hydroboration of aldehyde, ketone and imine substrates, with alkenes and alkynes not being reduced effectively. The use of microwave irradiation on the other hand has permitted alkenes
Activation and discovery of earth-abundant metal catalysts using sodium tert-butoxide
作者:Jamie H. Docherty、Jingying Peng、Andrew P. Dominey、Stephen P. Thomas
DOI:10.1038/nchem.2697
日期:2017.6
NaOtBu — an alkoxide salt — enables simple access to low-oxidation-state catalysis using sustainable first-row transition metals (Fe, Co, Mn, Ni). The approach works across a widerange of reductive alkene and alkyne functionlization reactions including hydroboration, hydrosilylation, hydrogenation, hydrovinylation and [2π+2π] cyclization reactions.