subsequent hydrorhodation of alkynes to provide vinylrhodium intermediates (RCHCH−[Rh]−SAr). In contrast, PdCl2(PhCN)2-catalyzed hydrothiolation of aromatic alkynes (ArC⋮CH) takes place to give the corresponding Markovnikov adducts (R(ArS)CCH2) with excellent regioselectivity, probably via thiopalladation of alkynes by palladium sulfide species (ArS−[Pd]−Cl), which may be formed by ligand-exchange reaction
Palladium(0)-catalyzed thioboration of terminal alkynes with 9-(alkylthio)-9-borabicyclo[3.3.1]nonane derivatives: stereoselective synthesis of vinyl sulfides via the thioboration-cross-coupling sequence
The addition of 9-(alkylthio)-9-borabicyclo[3.3.1]nonanes (9-(RS)-9-BBN) 1 to terminal alkynes was catalyzed by Pd(PPh 3 ) 4 3 mol %) to produce 9-[(Z)-2-(alkylthio)-1-alkenyl]-9-BBN derivatives 2 in high yields. The reactions were highly regio- and stereoselective, and their conditions were sufficiently mild that a variety of functionalized alkenylboranes 2 with defined stereochemistry were readily
Alkyne Hydrothiolation Catalyzed by a Dichlorobis(aminophosphine) Complex of Palladium: Selective Formation of cis-Configured Vinyl Thioethers
作者:Roman Gerber、Christian M. Frech
DOI:10.1002/chem.201200388
日期:2012.7.16
Cis all round: Dichlorobis[1‐(dicyclohexylphosphanyl)piperidine]palladium, [(P(NC5H10)(C6H11)2})2Pd(Cl)2], is a highly efficient alkynehydrothiolation catalyst and the first generally applicable system that selectively generates cis‐configured anti‐Markovnikov adducts in excellent yields within only a few minutes at 120 °C in the presence of only 0.05 mol % of the catalyst (see scheme).
全面顺产:二氯双[1-(二环己基膦酰基)哌啶]钯,[[P (NC 5 H 10)(C 6 H 11) 2 }) 2 Pd(Cl) 2 ]是一种高效的炔烃加氢硫基化催化剂,第一个普遍适用的系统,仅在0.05 mol%的催化剂存在下,在120°C的情况下,仅需几分钟即可选择性地以优异的收率生成顺式构型的反马氏复合物(见方案)。
Platinum-catalyzed highly selective thiocarbonylation of acetylenes with thiols and carbon monoxide
A novel carbonylative addition of thiols (RSH) to terminal acetylenes (R′–CCH) takes place successfully in the presence of platinum catalysts under the pressure of carbonmonoxide, providing α,β-unsaturated thioesters (R′–C(C(O)SR)CH2) in good yields regioselectively. This ‘hydrothiocarbonylation’ reaction of acetylenes may include the formation of the platinum sulfide complex as key species.
metal catalysts in the catalytic additions of a variety of P(O)-H bonds and an S-H bond to alkynes, affording regio- and stereoselectively both the Markovnikov and the anti-Markovnikov adducts, respectively, in high yields. A related five-coordinate hydrido nickel complex in the catalysis is successfully isolated, which can react readily with an alkyne to give the addition products.
廉价的镍催化剂在催化加成各种 P(O)-H 键和 SH 键到炔烃时比相应的贵金属催化剂更具反应性,提供区域和立体选择性的马尔科夫尼科夫和反马尔科夫尼科夫加合物,分别以高产。催化剂中相关的五配位氢化镍配合物被成功分离,它可以很容易地与炔烃反应生成加成产物。