Reissert reaction, modified

The classic Reissert indole synthesis, involving the reductive cyclization of o-ni-trophenylpyruvic acid, has been used for synthesis of 2-ethoxycarbonyl-4-alkoxymethylindo-les.92 The modified Reissert reaction, involving the reductive cyclization of an o-nitrophenyl acetoaldehyde, has been adapted to solid-phase synthesis.93... 

Aluminum chloride trimethylsilyl cyanide Modified Reissert reaction... 

Modified conditions have been developed for the preparation of cyanoheteroarenes from hetero-arene Woxides by the Reissert-Henze reaction, using TMSCN and DBU (Equation (9)). DBU as base is much more productive than triethylamine, which gave only 37% yield in 180 minutes compared to 76% in 40 minutes for the example shown <92H(33)2l l >. The use of tri- -butyltin cyanide with benzoyl chloride for the preparation of Reissert compounds when applied to phthalazine gave... 

Generally, the use of other heterocycles besides quinoline would be considered modifications of the original Reissert protocol. This reaction has been extended to convert an acyl chloride into an aldehyde through a one-pot process by adding the acyl chloride to a solution of quinoline and hydrocyanic acid, and subsequent steam distillation of the entire mixture with sulfuric acid. In addition, the formation of the Reissert compound has been modified to occur enantioselectively using TMSCN as the nucleophilic species in the presence of a Lewis acid-Lewis base bifunctional catalyst. Moreover, tri-n-butyltin cyanide and acetone cyanohydrin are also used for the preparation of the Reissert compounds. 

Another class of useful terpy synthons are carbonitrile-substituted terpyridines. Incorporation of a carbonitrile group at the 6- and 6 -positions of terpy can be achieved from the pyridine di-N-oxide, using a modified Reissert-Henze reaction with Me3Si(CN) and an acyl-chloride to provide the 6,6 -di(carbonitrile)terpyridine (4) [31, 32],... 

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