Acylsilanes and their applications in organic chemistry

Abstract

Estudos sobre o emprego de acilsilanos em rotas sintéticas e as novas metodologias de preparação desenvolvidas nos últimos anos, tornaram estes organo-silanos importantes reagentes para síntese de compostos orgânicos. Esta revisão apresenta algumas aplicações recentes e vários métodos desenvolvidos para síntese de acilsilanos. Current studies concerning the use of acylsilanes in a variety of organic synthetic routes and the improved methodologies of their preparation have turned organosilanes into important reagents for organic chemistry. This review discusses the recent employment of acylsilanes in organic synthesis and also effective methods for their preparation.

Yeast‐Mediated Stereoselective Synthesis

“…The reduction of acetyltrimethylsilane [387,388] by immobilized baker's yeast using two different ionic liquid buffer systems was studied in more detail, and the effects of temperature and pH were investigated. Finally high yields (>99%) and superior enantioselectivity (ee > 99.9%) could be obtained [382].…”

Reactions of an Isolable Dialkylsilylene with Aroyl Chlorides. A New Route to Aroylsilanes

“…Acylsilanes or α-silyl ketones have been known as a unique class of silicon compounds [1][2][3][4][5][6][7][8][9], showing remarkably red-red shifted n→π* transition bands [1,2] and being useful as distinct reagents in organic synthesis [4][5][6][10][11][12][13][14][15][16][17][18][19]. Most of all, acyltris(trimethylsilyl)silanes are of particular importance, which were utilized for the synthesis of the first stable silicon-carbon doubly bonded compounds (silenes) [20,21].…”

“…The direct reaction of a silylmetal with an acyl halide afforded the corresponding acylsilanes, but the yields were usually low due to the undesired secondary reactions [22,23]. The oxidation of α-silyl alcohols using ordinary oxidizing reagents often leads to the corresponding aldehydes [5]. The first successful synthesis of an aroylsilane was achieved by using an elaborate two-step route in good yields (Equation (1)) [22], while it is not applicable for the synthesis of alkanoylsilanes.…”

Organocatalytic asymmetric Michael reaction with acylsilane donors

“…Since their discovery by Brook in 1957, 1-3 acylsilanes have been the one of the most powerful and efficient compounds that have the silicon directly attached to the carbonyl group, exhibiting particular physical and chemical properties, [4][5][6][7][8] so that they can be easily transformed into many different derivatives in one pot, such as acid, 9-12 ketone, [13][14][15] alcohol, 16,17 aldehyde, 11,18,19 cyanogen, 20 amide 12,20,21 and ester. 20,22 In addition to these radical reactions, a great deal of effort has been devoted to the development of various other kinds of acylsilane reactions, for instance, stereocontrolled nucleophilic additions, 23 stereocontrolled aldol reactions, 24 cyclization, 25 coupling reaction, 26 α-halogenations, 3 and enantioselective reduction.…”