A-Alkoxynitriles

Similar results are observed with Grignard reagents and a-alkoxynitriles [91] and also with allylmagnesium bromide and various nitriles [83,92]. 

Asym. synthesis. A stirred soln. of startg. optically pure dioxane (prepared from (S)-( + )-butane-l,3-diol) and 4 eqs. of ethyl bromozinc-acetate (prepared from ethyl bromoacetate and Zn-Cu couple) in methylene chloride at —78° treated with 3 eqs. TiCl4, and quenched with 10% NaHC03 when reaction complete ca. 1 h) - product. Y 82% (diastereomer ratio 3.0 1). F.e. with racemic acetals s. T. Basile et al., J. Chem. Soc. Chem. Commun. 1989, 596-7 chiral a-alkoxynitriles with Me3SiCN/TiCl4 s. A. Solladie-Cavallo et al.. Tetrahedron Letters 29, 2955-8 (1988). 

Acylcyanides Acylimines Acylisocyanides 1-Alkoxyazomethines 1-Alkoxyenamines a-Alkoxynitriles Enehydroxyl amines... 

As mentioned above, the heterocycles can be easily metalated with a variety of bases. The oxazole ring and the benzoxazole ring can be metalated at C2 with a variety of strong bases. The major limitation of metalated oxazoles and benzoxazoles is their equilibrium with an open chain p-alkoxynitrile (see Section 6.3.1). In the ring-closed form, the oxazole is nucleophilic at C2. In the open chain form, the anion is nucleophilic at C4. This dual reactivity of the oxazole anion can lead to undesired regiochemistry unless carefiilly monitored. 

Labeled a-aminocarboxylic acids from cyanohydrins via labeled a-prim-aminonitriles Hydroxycarboxylic acids from alkoxynitriles... 

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