A photochemical desilylation reaction with nearly quantilative yield and excellent selectivity between silyl alkyl ether and silyl enol ether is reported.
The reasons for facile double desilylation of 13-vertex carborane 1,2-Me_(2)Si(CH_(2))_(2)-1,2-C_(2)B_(11)H_(11)(2)are discussed in this article.New 13-and 14-vertex ruthenacarboranes bearing the same-CH_(2)SiMe_(2)CH...The reasons for facile double desilylation of 13-vertex carborane 1,2-Me_(2)Si(CH_(2))_(2)-1,2-C_(2)B_(11)H_(11)(2)are discussed in this article.New 13-and 14-vertex ruthenacarboranes bearing the same-CH_(2)SiMe_(2)CH_(2)-linkage have been prepared and structurally characterized for comparison.Structural analyses of 13-and 14-vertex heteroboranes as well as control experiments suggest that the facile double desilylation of 2 on silica gel can be attributed to the joint actions of several factors involving the high ring-strain of exo five-membered C_(4)Si ring,Lewis acidity of Si atom and Brønsted acidity of silica surface.展开更多
Three routes were designed to synthesize a n-conjugated aryleneethynylenesiloles dendron. With the desilylation of the disilole mono（silylethynyl） derivative in the presence of potassium carbonate （K2CO3）, the sil...Three routes were designed to synthesize a n-conjugated aryleneethynylenesiloles dendron. With the desilylation of the disilole mono（silylethynyl） derivative in the presence of potassium carbonate （K2CO3）, the silole-containing oligomer has been successfully synthesized without impact on the Si-（CH3）2 group. The disilole mono- （silylethynyl） derivative was prepared by means of the Sonogashira heterocoupling reaction between the diacetylene compound and asymmetrical silole, catalyzed by the dichloro bis（triphenylphosphine）palladium, in a divergent synthesis. Due to their steric effect and triethynylbenzene self-coupling Glaser reaction, the endeavour to prepare the dendron by controlling the molar ratio of asymmetrical silole and 1,3,5-triethynylbenzene was failed. The another attempt to prepare the dendron by different desilylation condition of triisopropylsilyl group and trimethylsilyl group was also failed, the desilylation of Si-（CH3）2 group in silacyclopentadiene unit was also easily accomplished in the presence of tetrabutylammonium fluoride（Bu4NF）, whereas no reaction occurred when K2CO3 was used instead of Bu4NF.展开更多
Recent advances in the desilylative acylation of 1-alkenylsilanes with acid anhydrides under transition metal catalysis are summarized.This catalytic desilylative acylation of 1-alkenylsilanes provides an efficient ro...Recent advances in the desilylative acylation of 1-alkenylsilanes with acid anhydrides under transition metal catalysis are summarized.This catalytic desilylative acylation of 1-alkenylsilanes provides an efficient route toα,β-unsaturated ketones by using rhodium or iridium as the catalyst.Moreover,various one pot sequence reactions have been developed,which can synthesizeα,β-unsaturated ketones from simple starting materials in an economic way.Additionally,this approach is applied to the asymmetric synthesis of atropisomers possessing silanol groups with excellent enantioselectivity.展开更多
基金the National Natural Science Foundation of China (Grant No. 29972018) for financial support.
文摘A photochemical desilylation reaction with nearly quantilative yield and excellent selectivity between silyl alkyl ether and silyl enol ether is reported.
基金The work described in this paper was supported by grants from the Research Grants Council of the Hong Kong Special Administration Region(Nos.404610 and CUHK7/CRF/12G).
文摘The reasons for facile double desilylation of 13-vertex carborane 1,2-Me_(2)Si(CH_(2))_(2)-1,2-C_(2)B_(11)H_(11)(2)are discussed in this article.New 13-and 14-vertex ruthenacarboranes bearing the same-CH_(2)SiMe_(2)CH_(2)-linkage have been prepared and structurally characterized for comparison.Structural analyses of 13-and 14-vertex heteroboranes as well as control experiments suggest that the facile double desilylation of 2 on silica gel can be attributed to the joint actions of several factors involving the high ring-strain of exo five-membered C_(4)Si ring,Lewis acidity of Si atom and Brønsted acidity of silica surface.
基金supported by National Natural Science Foundation of China （Nos. 20872035, 21076078）, and Specialized Research Fund for the Doctoral Program of Higher Education （No. 20070251018）.
文摘Three routes were designed to synthesize a n-conjugated aryleneethynylenesiloles dendron. With the desilylation of the disilole mono（silylethynyl） derivative in the presence of potassium carbonate （K2CO3）, the silole-containing oligomer has been successfully synthesized without impact on the Si-（CH3）2 group. The disilole mono- （silylethynyl） derivative was prepared by means of the Sonogashira heterocoupling reaction between the diacetylene compound and asymmetrical silole, catalyzed by the dichloro bis（triphenylphosphine）palladium, in a divergent synthesis. Due to their steric effect and triethynylbenzene self-coupling Glaser reaction, the endeavour to prepare the dendron by controlling the molar ratio of asymmetrical silole and 1,3,5-triethynylbenzene was failed. The another attempt to prepare the dendron by different desilylation condition of triisopropylsilyl group and trimethylsilyl group was also failed, the desilylation of Si-（CH3）2 group in silacyclopentadiene unit was also easily accomplished in the presence of tetrabutylammonium fluoride（Bu4NF）, whereas no reaction occurred when K2CO3 was used instead of Bu4NF.
基金Financial support from National Natural Science Foundation of China(No.21871053)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(No.2019R01005)the Open Research Fund of School of Chemistry and Chemical Engineering,Henan Normal University(No.2020ZD04)。
文摘Recent advances in the desilylative acylation of 1-alkenylsilanes with acid anhydrides under transition metal catalysis are summarized.This catalytic desilylative acylation of 1-alkenylsilanes provides an efficient route toα,β-unsaturated ketones by using rhodium or iridium as the catalyst.Moreover,various one pot sequence reactions have been developed,which can synthesizeα,β-unsaturated ketones from simple starting materials in an economic way.Additionally,this approach is applied to the asymmetric synthesis of atropisomers possessing silanol groups with excellent enantioselectivity.
