From cyanohydrins

The formation of hydantoin (2) from carbonyl compound 1 with potassium cyanide and ammonium carbonate or from cyanohydrin 3 and ammonium carbonate is referred to as... 

Other examples of the ElcB pathway are benzyne formation from C6HsF (cf. p. 174), reversal of simple nucleophilic addition to 0=0, e.g. base-induced elimination of HCN from cyanohydrins (20 cf. p. 212),... 

Zandbergen, P., van den Nieuwendijk, A.M.C.H., Brussee, J. et al. (1992) A one-pot reduction-transimition-reduction synthesis of JV-substituted /8-ethanolamines from cyanohydrins. Tetrahedron, 48, 3977-3982. 

Fig. 3. Examples of bioactive compounds synthesised from cyanohydrins...

Formation of hydantoins from carbonyl compounds with potassium cyanide (KCN) and ammonium carbonate [(NH4)2C03] or from cyanohydrins and ammonium carbonate. It belongs to the category of multiple component reaction (MCR). 

A large number of the most important modem insecticides are derived from cyanohydrins. Especially some esters formed from enantiopure cyanohydrins and chrysanthemum acid derivatives are known to be very potent [201]. Nowadays, the formation of 3-phenoxybenzaldehyde cyanohydrin is performed in a biocatalytic industrial process using Me HNL or 7/bHNL isolated from mbber trees (Hevea... 

Cyclopropylimines are usually generated by reduction of nitriles or condensation of carbonyl compounds with amines. An alternative to this process involves the generation of cyclopropylinunoni-um salts such as (209) at room temperature from cyanohydrin equivalent (208 Scheme 49). ... 

The carbanion (1) can be generated independently from cyanohydrins and can be added to the double bond of a,3-unsaturated ketones, esters and nitriles by an irreversible reaction which ultimately leads to y-diketones, 4-oxocarboxylic esters and4-oxonitriles. ... 

Acyl anion synthons derived from cyanohydrins may be generated catalytically by cyanide ion via the Stetter reaction " However, further reaction with electrophiles is confined to carbonyl compounds and Michael acceptors. 

Amines. Chiral a-amino acids are obtained from cyanohydrins via a Mitsunobu reaction employing A-f-butoxycarbonyl-A-(2-trimethylsilyl)ethylsulfonamide as the nucleophile. The a-aminonitrile derivatives thus generated are hydrolyzed with acid. By means of an intramolecular displacement (3-hydroxy acids are transformed into (3-amino acids. Thus, subjecting the derived 0-benzylhydroxamides to Mitsunobu reaction conditions leads to (3-lactams which are readily processed (LiOH H, Pd/C). 

A -Acyl-oxazolidin-2-ones, as 203, are widely used in aldol reactions, however an unprecedented use of the aldol adducts for a stereoselective synthesis of trisubstituted a, 3-unsaturated amides and acids was reported. The yy -aldol adduct 204 underwent clean elimination upon treatment with KHMDS and afforded the E -olefin 205 with a 97% ds. The reaction was wide in scope but with a loss in selectivity using a,P-unsaturated or chiral aldehydes <05OBC2976>. This synthetic approach found immediate application in the synthesis of semiplenamide C 206 <05TL5547>. Oxazolidin-2,4-diones 207, obtained from cyanohydrins, can be easily converted into the corresponding a-hydroxyamides 208 in a reaction that can be accelerated by microwaves <05T7247>. 

Silyl enamines have been prepared from cyanohydrins RR QOSiMcaiCN by reductive silylation with McaSiCl/Li. Photodesilylation by HCl gas in dry diethyl ether or by trimethylchlorosilane in methanol gave, after neutralization, the enamines, RR C=C(NH2)SiMc3 which were surprisingly stable. 

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