yields via the reactions of RE(CH2SiMe3)3(thf)2 with the proligand H2L in a single step. Mechanistic studies reveal that treatment of 1 with phenylacetylene could generate the active catalytic species: dinuclear rare-earth metal alkynides (L(thf)n[RE(μ-C≡CPh)]2L) (RE = Y(5a), n = 1; Yb(5c), n = 0), which could react with HSi(OEt)3 to produce the coupling product 4aa and the dinuclear rare-earth metal
Sodium triethylborohydride as a catalyst for the dehydrogenative silylation of terminal alkynes with hydrosilanes
作者:Maciej Skrodzki、Samanta Witomska、Piotr Pawluć
DOI:10.1039/c8dt00684a
日期:——
sodium triethylborohydride-catalyzed C(sp)–H bond silylation is reported. The reaction of aromatic and aliphatic alkynes with aromatic hydrosilanes and hydrosiloxanes proceeded in a highly selective manner to afford dehydrocoupling products. Competitive hydrosilylation of the terminalalkyne did not occur as a side-reaction. In view of the above it is remarkable that NaHBEt3 is commonly used as a reducing
B(C
<sub>6</sub>
F
<sub>5</sub>
)
<sub>3</sub>
/Amine‐Catalyzed C(sp)−H Silylation of Terminal Alkynes with Hydrosilanes: Experimental and Theoretical Studies
C(sp)−H silylation of a wide range of terminalalkynes with hydrosilanes by using a combination of B(C6F5)3 and an organic base such as triethylenediamine (DABCO). This protocol constitutes the first example of boron‐catalyzed C(sp)−H functionalization, offering a convenient route for the synthesis of a variety of alkynylsilanes. Experimental and computational studies have revealed that DABCO plays two
过渡金属催化的有机化合物的CH官能化已被证明是有机合成中有用的原子效率策略。相比之下,迄今为止,对于CHH功能化的基于主族元素的催化过程仍未得到充分研究。本文报道的是通过使用B(C 6 F 5)3的组合,各种末端炔烃与氢硅烷的催化C(sp)-H甲硅烷基化反应和有机碱,例如三乙二胺(DABCO)。该协议构成了硼催化的C(sp)-H功能化的第一个例子,为合成各种炔基硅烷提供了一条便捷的途径。实验和计算研究表明,DABCO在此催化转化中起着两个至关重要的作用(刘易斯碱和布朗斯台德碱)。
Dehydrogenative Coupling between Hydrosilanes and Alkynes Catalyzed by Alkoxides, Alkylmetals, and Metalamides
作者:Jun-ichi Ishikawa、Masayoshi Itoh
DOI:10.1006/jcat.1999.2530
日期:1999.7
selective dehydrogenative coupling reaction between phenylsilane and ethynylbenzene occurred in the presence of some homogeneous base catalysts such as alkoxides, alkylcompounds, and the amides of alkalimetals or barium. The order of the catalytic activities was Ba(OR)2>LiN(SiMe3)2∼n-BuLi>LiOEt. Barium alkoxide showed the highest activity and selectivity for the reaction, and gave the polymer poly[(p
This work reports a C(sp)-H silylation of terminalalkynes with hydrosilanes by using a molecular calcium hydride [(DIPPnacnac)CaH(thf)}2] (DIPPnacnac = CH(CMe)(2,6-iPr2-C6H3N)}2) as a catalyst. The reaction selectively afforded monoalkynylsilanes in high isolated yields with a broad substrate scope and high atom economy. A control experiment and kinetic studies were conducted to provide some insights