Lanthanide- and Actinide-Mediated Terminal Alkyne Hydrothiolation for the Catalytic Synthesis of Markovnikov Vinyl Sulfides
作者:Charles J. Weiss、Stephen D. Wobser、Tobin J. Marks
DOI:10.1021/om100697h
日期:2010.12.13
hydrothiolation product from the Sm center. Mechanistic findings indicate turnover-limiting alkyne insertion into the Sm−SR bond, followed by very rapid, thiol-induced M−C protonolysis to yield Markovnikov vinyl sulfides and regenerate the corresponding M−SR species. Comparisons of different substrates and metal complexes in catalyzing hydrothiolation reveal a strong dependence of hydrothiolation activity
使用Cp * 2 LnCH(TMS)2(Cp * = C 5 Me 5 ; Ln = La,Sm,Lu),通过脂族,苄基和芳族硫醇的马尔可夫涅夫选择性镧系元素和act系元素介导的末端炔烃分子间氢硫醇化反应, LN [N(TMS)2 ] 3(Ln为镧,钕,Y)中,Cp * 2的(CH 2 TMS)2,和Me 2 SiC颗粒'' 2所述的(CH 2 R)2(CP''= C 5我4; An = Th,R = TMS;详细研究了An = U,R = Ph)作为预催化剂。这些转化被证明是马尔可夫尼科夫选择性的,选择性高达> 99%。发现Cp * 2 SmCH(TMS)2介导的1-戊硫醇和1-己炔之间反应的动力学研究是催化剂浓度一级,炔烃浓度一级和硫醇浓度零级。炔烃-C≡C-H位置的氘标记显示k H / k D分别为有机Sm和有机Th催化过程的1.40(0.1)和1.35(0.1),以及硫醇介导的乙烯