Gold(III)-Catalyzed Cyanosilylation of Ketones and Aldehydes

Abstract

Gold(III) chloride was found to be a highly efficient catalyst for the cyanosilylation of various ketones and aldehydes. The reactions were complete within 30 minutes at room temperature in the presence of only one mol% gold(III) chloride, yielding the corresponding cyanohydrin trimethylsilyl ethers in very good yields. The isolated yields for the reactions of ketones were up to 98%, and the reactions of aldehydes gave 100% conversion, as monitored by 1 H NMR spectroscopy.

Mononuclear Aluminum Complexes as Precursors for Cyanosilylation of Carbonyl Compounds

“…Solvents such as n-hexane and toluene were dried using sodium metal and LiAlH 4 under an inert atmosphere. 1 H NMR (400 MHz and 600 MHz), 13 C{ 1 H} (100 MHz and 150 MHz), 19 F{ 1 H} (376 MHz), and 31 P{ 1 H} (243 MHz) spectra were recorded on the BRUKER ADVANCE III-400 MHz and 600 MHz spectrometer. Chemical shifts (δ ppm) and coupling constants (Hz) were reported in the standard fashion for the internal standard tetramethylsilane (TMS) (δ H = 0.00 ppm).…”

“…[18] Literature survey reveals that transition metal complexes-based catalytic systems have been widely employed in the cyanosilylation of aldehydes and ketones. [19][20][21][22] Main group metal complex catalysts are slowly gaining favor over transition metal complexes, owing to their abundant availability, low cost, non-toxic behavior, high reactivity, catalytic efficiency, and excellent selectivity. To date, there have only been limited examples in the literature of main group elements (Li, [23] Mg, [24] Al, [25] Ge, [26] Sn, [27] and Si [28] ) catalyzing the cyanosilylation of carbonyl compounds.…”

“…The transformation of α‐hydroxy nitrile derivatives into various intermediate compounds facilitates the synthesis of several building blocks such as α ‐hydroxy ketones, β ‐amino alcohols, and α ‐hydroxy acids, which are used in the production of fine chemicals, agrochemicals, and pharmaceuticals [18] . Literature survey reveals that transition metal complexes–based catalytic systems have been widely employed in the cyanosilylation of aldehydes and ketones [19–22] . Main group metal complex catalysts are slowly gaining favor over transition metal complexes, owing to their abundant availability, low cost, non‐toxic behavior, high reactivity, catalytic efficiency, and excellent selectivity.…”

Highly efficient chemo- and regioselective silylation of –OH groups and cyanosilylation of aldehydes promoted by TiCl2(OTf)–SiO2 as a new recyclable catalyst

“…These compounds are prepared from the reaction of carbonyl compounds with TMSCN, and many catalysts and reagents have been introduced to achieve this goal. Various Lewis acids [48][49][50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66], base catalysts [67][68][69][70], solid catalysts [71][72][73][74], organocatalysts [75][76][77][78][79][80][81], ionic liquids [82,83] and bifunctional catalysts [84][85][86][87] have been employed to furnish cyanosilylation of carbonyl compounds with TMSCN. Although many promising catalysts and reagents have been introduced to promote this reaction, there is much room for the design and preparation of new catalysts, which offer short reaction time, easier work-up and can be recycled simply without considerable loss of their catalytic abilities.…”