Application of Ni(II) complexes of air stable Schiff base functionalized <i>N</i>-heterocyclic carbene ligands as catalysts for the transfer hydrogenation of aliphatic ketones
作者:Samaila Abubakar、Muhammad D. Bala
DOI:10.1080/00958972.2018.1493199
日期:2018.9.17
complexes were utilized as catalysts for the catalytic transfer hydrogenation of aliphaticketones in 2-propanol as solvent and source of hydrogen. Based on 0.2 mol% catalyst concentration, the complexes showed activity for aliphaticketones and 100% conversion (turnover number of 500) for cyclohexanone and all the aromatic ketones tested. Graphical Abstract
Bidentate Ligands by Self-Assembly through Hydrogen Bonding: A General Room Temperature/Ambient Pressure Regioselective Hydroformylation of Terminal Alkenes
room temperature/ambient pressure regioselective hydroformylation of terminalalkenes with low catalyst loadings in good activity. The generality of this catalyst under these conditions was demonstrated for a wide range of structurally diverse alkenes equipped with many important functional groups. Thus, this practical and highly selective hydroformylation protocol, which omits the need for special pressure
derivatives) were found to undergo regioselective addition with a variety of aldehydes, ketones, esters and acid amides at the sterically more crowded terminal carbon of the ligated diene to give the (Z)-oxazirconacyclo-4-heptenes. Further addition of carbonyl compounds to the resulting oxametallacycle leads to adducts of (E)-1,3-dioxazircona-6-nonene structure when the precursor oxazirconacycloheptene has a
组类型的Zr 4金属-二烯配合物(η-C 5 H ^ 5)2(S-顺式-二烯)和Zr(η-C 5 H ^ 5)2 - (S-反式-二烯)(二烯=丁二烯,发现异戊二烯,戊二烯及其衍生物)在连接的二烯的空间更拥挤的末端碳上与多种醛,酮,酯和酰胺进行区域选择性加成,得到(Z)-氧杂碳环环-4-庚烯。将羰基化合物进一步添加到生成的oxametallacycle中会导致(E)-1,3-dioxazircona-6-nonene结构,当前体恶唑烷并环庚烯在C(5)位置具有较小的氢基团时。高选择性,三组分,顺序添加首先通过用Zr(C 5 H 5)2(二烯)/酯,Zr(C 5 H 5)2(二烯/烯烃和Zr( C 5 -H 5)2(二烯)/炔烃加合物。
Photochemical deconjugation of α,β-unsaturated ketones
作者:Stephen L. Eng、Roland Ricard、Calvin S. K. Wan、Alan C. Weedon
DOI:10.1039/c39830000236
日期:——
relative quantum yield of deconjugation as a function of base and solvent; the results indicate two competing mechanism for the reketonization of the intermediate dienols, one involving a thermal 1,5-sigmatropichydrogenshift, and the other base-catalysed proton trabnsfer.
1-Trimethylsilyl 2-methylcyclopropane cis or trans resulting from the silylation of 1-bromo 1-propene is a convenient regio- and stereospecific precursor of β,γ-unsaturated Z or E ketones and 2-butene sulfonic acid.