18026-73-8Relevant academic research and scientific papers
Silver-promoted desilylation catalyzed by ortho- and allosteric cucurbiturils
Lu, Xiaoyong,Masson, Eric
supporting information; experimental part, p. 2310 - 2313 (2010/08/04)
Cucurbit[6]-, [7]-, and [8]uril can catalyze the silver(I)-promoted desilylation of trimethylsilylalkynyl-containing pseudorotaxanes by stabilizing a key π-alkynyl silver intermediate through favorable interactions between the metallic cation and the cavi
Catalytic asymmetric Mannich-type reactions activated by ZnF2 chiral diamine in aqueous media
Hamada, Tomoaki,Manabe, Kei,Kobayashi, Shu
, p. 1205 - 1215 (2007/10/03)
Catalytic asymmetric Mannich-type reactions of an α-hydrazono ester with silicon enolates in aqueous media have been developed by using ZnF 2 and chiral diamines as catalysts. In these reactions, both Zn 2+ and a fluoride anion were necessary to achieve high yields and enantioselectivities. suggesting a double activation mechanism, in which Zn 2+ activates the α-hydrazono ester and the fluoride anion simultaneously activates the silicon enolate. When chiral diamine ligands bearing methoxy-substituted aromatic rings were employed, the reactions in aqueous THF were markedly accelerated. Furthermore, the use of these diamines facilitated the asymmetric Mannich-type reactions in water without any organic cosolvents. It is noteworthy that either syn or anti adducts were stereospecifically obtained from (E) or (Z)-silicon enolates, respectively. Interestingly, these reactions proceeded smoothly only in the presence of water. On the basis of several experimental results, it can be concluded that the reaction mechanism is likely to be a fluoride-catalyzed one, in which the ZnF2 chiral diamine complex is regenerated from the Me3SiF formed during the reaction.
Preparation of a new class of cleavable surfactants based on the silicon-carbon bond
Noronha, Glenn,Nguyen, Khanhlinh T.
, p. 4935 - 4938 (2007/10/03)
The ability of silicon to direct electrophiles to the ipso-position is used in developing a new class of cleavable amphiphiles containing an acid labile silicon-carbon (aromatic) bond. The synthesis of these amphiphiles is carried out in four steps to yie
