Viehe’s salt

Cyanation of aromatics.1 Viehe s salt (1) effects electrophilic cyanation of aromatic or heteroaromatic systems. 

Treating the dilithium salt of o-hydroxybenzeneselenol, generated in situ from 2-bromophenol 253, with (dichloro-methylene)dimethylimmonium chloride (Viehe s salt), followed by sodium hydrogenselenide gave benzo-l,3-oxa-selenole-2-selone 153 (Scheme 13) <2004JOC9319>. 

The vicinal diol 216, prepared in 10 steps from quinic acid, was elaborated into V-alkylated 2-epi-valienamines 217 in variable (16-98%) yield by reaction with Viehe s salt followed by Pd(0)-catalysed coupling with a range of primary e.g. R = H = Et, Bu, Hept, Oct, cyclohexyl, Bn) and secondary amines e.g. R = R = Bu, cyclohexyl, Pr). Carbocyclic influenza neuraminidase inhibitors 219 (n = 3-8) with a cyclic amine side-chain have also been prepared via Pd(0)-catalysed coupling of acetate 218 with the corresponding cyclic amines. The use of pentafunctional quinic acid as a polyoxygenated scaffold for combinatorial synthesis has also been described. ... 

A one-pot synthesis of bromodeoxy carbamates has been achieved using Viehe s salt followed by treatment with lithium bromide. Thus... 

Dichloromethylene) -dimethylammonium chloride (Vilsmeier reagent/Viehe s salt)... 

Viehe s salt reacts with secondary hydroxy groups to yield the inverted chloro-deoxy compounds. Thus the 3-hydroxy-glucoside (15) gives rise to the 3-chloro-3-deoxy-alloside (16). With methyl <-D-lyxofuranoside the 2-0-carbamoyl-3,5-dichloro-derivative (17) was produced. The products were used in the gynthesis of deoxy and amino sugars using conventional methods. The full paper on the... 

N,N-diethylammonium chloride (Viehe s salt) with sugars has been... 

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