Disclosed herein is the first general chemo- and site-selective alkylation of C-Br bonds in the presence of COTf, C-Cl and other potentially reactive functional groups, using the air-, moisture-, and thermally stable dinuclear PdI catalyst, [Pd(μ-I)PtBu3 ]2 . The bromo-selectivity is independent of the substrate and the relative positioning of the competing reaction sites, and as such fully predictable
A number of organozinc reagents was found to react with tetramethylthiuramdisulfide [(Me 2 NCS 2 ) 2 ] giving dithiocarbamates with complete retention of configuration in the case of chiral compounds.
Silicon in organic synthesis. Stereoselective synthesis of some insect sex pheromones
作者:T.H. Chan、K. Koumaglo
DOI:10.1016/0022-328x(85)87361-7
日期:1985.4
stereo-selectively the γ-product with trans-stereochemistry at the double bond. The trans-vinylsilanes are transformed stereoselectively to Z-vinyl iodides. Coupling of the vinyl iodides with organometallic reagents gives Z-alkenes. This approach has been applied to the synthesis of several insect sexpheromones.
Pincer Thioamide and Pincer Thioimide Palladium Complexes Catalyze Highly Efficient Negishi Coupling of Primary and Secondary Alkyl Zinc Reagents at Room Temperature
作者:Haibo Wang、Jing Liu、Yi Deng、Tianyin Min、Ganxiang Yu、Xiaojun Wu、Zhen Yang、Aiwen Lei
DOI:10.1002/chem.200801860
日期:2009.1.26
structures of complexes 2 and 3 were confirmed by X‐ray analysis. Both complexes are efficient catalysts for Negishicouplings involving primary and secondary alkyl zinc reagents bearing β‐hydrogen atoms. At a concentration of 0.1–0.5 mol % both catalysts readily promoted reactions at roomtemperature or even at 0 °C. The operational simplicity of these processes, in conjunction with the easy accessibility
Stereoselective synthesis of α-alkylidene- and substituted alkylidene-γ-lactones
作者:Jakub Častulı́k、Ctibor Mazal
DOI:10.1016/s0040-4039(00)00252-5
日期:2000.4
Cross-coupling reactions of (E)- and (Z)-tosylates of α-hydroxymethylene-γ-butyrolactone with aryl, heteroaryl, alkyl, and alkynylzinc chlorides under Pd(PPh3)4 catalysis were found to be a suitable synthetic method for stereoselective preparation of α-alkylidene- and substituted alkylidene-γ-lactones. The reactions, conducted under mild conditions, proceed with high stereoselectivity and moderate yields.