Reissert-Henze reaction, nucleophiles

One can extend the strategy employed in the Reissert-Henze reaction to nucleophiles other than cyanide. Phosphorus-based systems were employed in the... 

Even poor nucleophiles such as the amides 46 can react with azines in the presence of alkynes as activating agents [59, 60]. Various nucleophiles (including alkoxides, thiols, amines and nitrogen heterocycles) were recently employed in a related process with Ai-oxide azaindoles (Reissert-Henze reaction. Scheme 10). In the process, the oxygen is alkylated with dimethyl sulfate and, after the nucleophilic attack, methanol is released to aromatize the initial adduct [61,62]. Following similar mechanistic trends, V-heteroatom-activated azines afford the corresponding substituted adducts. Likewise, W-tosylated isoquinoline [63, 64] and W-fluoropyridinium salts [65] are also reactive substrates in Reissert-Henze type processes. 

Later on, trimethylsilylcyanide and diethyl phosphorocyanidate (DEPC) were also found to activate the A -oxide in the above the Reissert-Henze reaction. In addition, lithium diethylphosphite was used as the nucleophile other than cyanide as shown in the transformation of N-methoxy pyridine 315 into the diethylphosphonate 316. ... 

A -Activation in quinolines (through acylation) and pyridines (through etherification of the respective A-oxides) allows the nucleophilic addition of [ CJcyanide to the position alpha to nitrogen, resulting in the formation of 2-[ C]cyanoquinolines and [2- C]-cyanopyridines (Reissert-Henze reaction). This has been exploited for the preparation of the 2-[ C]cyano derivative 21 in good yield ". ... 

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