A highly efficient PtO2/PTSA catalyst system for the hydration of a wide array of alkynes was developed. This method proved to be compatible with a large range of functional groups and the ketone products were obtained in high yields. The scope of this methodology was also extended to the synthesis of 3-aryl-isochromenones, -indoles and -benzofurans.
A novel strategy involving Cu‐catalyzedoxidative transformation of ketone‐derived hydrazone moiety to various synthetic valuable internal alkynes and diynes has been developed. This method features inexpensive metal catalyst, green oxidant, good functional group tolerance, high regioselectivity and readily available starting materials. Oxidative deprotonation reactions were carried out to form internal
DUAL SITE CATALYST FOR MILD, SELECTIVE NITRILE REDUCTION
申请人:University of Southern California
公开号:US20160145193A1
公开(公告)日:2016-05-26
A ruthenium bis(pyrazolyl)borate scaffold that enables cooperative reduction reactivity in which boron and ruthenium centers work in concert to effect selective nitrile reduction is provided. The pre-catalyst compound [κ
3
-(1-pz)
2
HB(N═CHCH
3
)]Ru(cymene)
−
TfO
−
(pz=pyrazolyl) was synthesized using readily-available materials through a straightforward route, thus making it an appealing catalyst for a number of reactions.
Palladium-catalyzed reactions of aryl iodides with trimethylsilylacetylenes and disubstituted alkynes: the synthesis of diarylacetylenes and triarylethylenes
trimethylsilylacetylene in the presence of 3 equiv. of sodiummethoxide and 5 mol% of Pd(PPh3)4 under refluxing methanol for 6 h gave diarylacetylene in good chemical yields. When the catalyst was replaced by Pd(dba)2 and 5 equiv. of aryl iodide were added under the same reaction conditions, triarylethylenes were obtained in 70–85% yields. Only the sterically hindered o-methoxyiodobenzene and 2-iodothiophene
efficient copper-catalyzed radical cascade cyclization strategy was developed, by which a wide variety of 3-sulfonyl substituted indenones were prepared in one pot via reaction of 2-alkynylbenzonitriles with sulfonyl hydrazides in the presence of TBHP and CuI under mild reaction conditions. Much more importantly, the 3-sulfonyl indenones, synthesized through our newly developed copper-catalyzed radical