Butyl cyanide reduction

Addition to Carbon-Heteroatom Multiple Bonds. The behavior of r-BuLi in reactions with carbon-heteroatom r-bonds is relatively unremarkable and parallels that of other organolithium reagents. Even in cases where steric hindrance might be expected to lead to difficulties, product yields are reasonable. Thus, for example, tri-f-butylcarbinol (3-r-butyl-2,2,4,4-tetramethyl-3-pentanol) may be prepared by addition of r-BuLi to di-r-butyl ketone (2,2,4,4-tetramethyl-3-pentanone), although there is a significant amount of reduction in this case, and V-lithio-di-r-butylimines may be generated by addition of r-BuLi to r-butyl cyanide. ... 

Reductive metallation of aldehydes (but not ketones) by tri-n-butyl-(trimethyisilyl)stannane to yield a-hydroxystannanes is catalysed by tetra-n-butylammonium cyanide [15]. Other phase-transfer catalysts are not as effective and solvents, other than tetrahydrofuran, generally give poorer conversions. Use of a chiral catalyst induced 24% ee with 3-phenylpropanal. 

A third route developed by this group started with the commercially available alcohol 32," a compound which has also been the subject of considerable process development due to its use as a common intermediate in the synthesis of several HMGR inhibitors.Conversion of 32 to the 4-halo or 4-nitrobenzenesulfonate 33 followed by displacement with sodium cyanide provided 34 in 90% yield, which is the z-butyl-ester analog of 29. It was noted that this procedure was most scaleable employing the 4-chlorobenzenesulfonate 33a due to the instability of the 4-bromo and 4-nitro-analogs to aqueous hydrolysis. Ra-Ni reduction as before provided the fully elaborated side-chain 35 as the f-butyl ester (Scheme 8). 

Quallich and Woodall described the first asymmetric synthesis utilizing a catalytic enantioselective reduction of the ketoester 35 with (S)-terahydro-l-methyl-3,3-diphenyl-lH,3W-pyrrolo[l,2-c][l,3.2]oxazaborole (CBS) to give the desired hydroxyester 36 (90% ee). After mesylation, Sn2 displacement with a higher-order cuprate derived from copper cyanide gave the diaryl r-butyl ester 37 with good chirality transfer. Intramolecular Friedel-Crafts cyclization gave the tetralone 31 in 90% ee (Scheme 7). ... 

This important fragrance material probably was introduced in commercial perfumery during the first decade of the twentieth century with the discovery of the Bouveault-Blanc reduction of esters by sodium and an alcohol (10). This is the first of several methods of preparation shown in Figure 16. Large quantities of phenylethyl alcohol were made by sodium reduction of butyl phenylacetate in normal butanol. The basic raw materials were readily available at low cost from benzyl chloride, sodium cyanide and fermentation butanol. 

We present at the end of this section, several isolated examples of trinuclear cyanide-bridged complexes that do not fall within the two major classes of compounds. The first group of such complexes is based on a triangular cluster core. For example, Evans et al., (127) obtained [(Cp )2Sm CNR)( j,-CN)]3 (R = hexyl, tert-butyl) [Fig. 19(a)] from a reductive cleavage of the isocyanide CNR ligand by Cp 2Sm (thf)2. Moreover, the same group later demonstrated the preparation of such trinuclear complexes by isocyanide cleavage with Cp 3Sm ... 

Acid-catalyzed addition of aliphatic, aromatic or heteroaromatic cyanohydrins to ethyl vinyl ether, n-butyl vinyl ether or dihydro-4//-pyran provides base stable, protected cyanohydrin derivatives. Phase transfer catalyzed alkylation of aliphatic cyanohydrins with allylic bromides gave a-substituted a-allyl-oxyacetonitrile. Carbonyl compounds react wiA cyanide under phase transfer catalysis to give cyanohydrin anions, which are trapped by an acyl chloride or ethyl chloroformate to give acyl- or alkoxycarbonyl-protected cyanohydrins respectively. The reduction of the carbonyl group of an acyl cyanide by NaBH4 under phase transfer conditions followed by esterification serves as an alternative route to aldehyde-derived cyanohydrin esters. ... 

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