The use of trimethylsilyl cyanide (TMSCN) as a reagent for the direct formation of trimethylsilyl cyanohydrin ethers 3 from ketones is reported. The advantages in using TMSCN as opposed to hydrogen cyanide are illustrated by the formation of cyanohydrin ethers of ketones that do not form stable cyanohydrins. The reduction of derivatives 3 with lithium aluminum hydride is reported to afford /3-aminomethyl alcohols 4 in good yield. The combined carbonyl derivatization-reduction sequence should afford a general synthesis of 4 useful in executing ring expansion reactions.

Vanadium haloperoxidase enzymes catalyze the oxidation of halide ions by hydrogen peroxide, producing an oxidized intermediate, which can halogenate an organic substrate or react with a second equivalent of hydrogen peroxide to produce dioxygen. Haloperoxidases are thought to be involved in the biogenesis of halogenated natural products isolated from marine organisms, including indoles and terpenes, of which many are selectively oxidized or halogenated. Little has been shown concerning the ability of the marine haloperoxidases to catalyze regioselective reactions. Here we report the regiospecific bromoperoxidative oxidation of 1,3-di-tert-butylindole by V-BrPO from the marine algae Ascophyllum nodosum and Corallina officinalis. Both enzymes catalyze the regiospecific oxidation of 1,3-di-tert-butylindole in a reaction requiring both H(2)O(2) and Br(-) as substrates, but which produce the unbrominated 1,3-di-tert-butyl-2-indolinone product exclusively, in near quantitative yield (i.e. one H(2)O(2) consumed per product). By contrast, reactions with the controlled addition of aqueous bromine solution (HOBr = Br(2) = Br(3)(-)) produce three monobromo and one dibromo-2-indolinone products, all of which differ from the V-BrPO-catalyzed product. Further, reactivities of 1,3-di-tert-butyl-2-indolinone with both aqueous bromine and V-BrPO differ significantly and shed light onto the possible nature of the oxidizing intermediate. This is the first example of a regiospecific bromination by a vanadium haloperoxidase and further extends their usefulness as catalysts.

Stmmary A wide variety of aldehydes and ketones reacts with trimethylsilyl cyanide under both thermal and catalytic conditions to give a-silyloxy nitriles which may be useful intermediates and protective groups in organic synthesis.WE have observed that trimethylsilyl cyanide (Me,SiCN)I in an apparently uncatalysed process adds readily to aldehydes affording the cyanosilylated adducts (1; R1 = alkyl, R* = H) in good yields. The only contaminant in the addition process is the silyl enol ether which does not appear to be derived from (1). The reaction may be simply carried out by combining equimolar amounts of aldehyde and Me,SiCN and heating for several hours in the absence of added solvent. Ketones, on the other hand, react slowly with Me,SiCN, e.g. cyclohexanone requires heating at 115' for 24 h for complete reaction.We have discovered that minute amounts of zinc iodide dramatically enhance the rate of Me,SiCN carbonyl addition while simultaneously suppressing the formation of silyl enol ether. Using this method of catalysis, a wide variety of aldehydes and ketones may be cyanosilylated rapidly and

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