Demjanov rearrangement mechanism

The mechanism for the Demjanov reaction is a well accepted mechanism. The formation of the diazonium occurs as outlined. Reaction of the amine 1 with activated NOX 12 (X is thought to be ONO) delivers the A-nitroso compound 13, which undergoes rearrangement to provide hydroxyl-diazo material 14. Protonation of 14 and loss of water provides the diazonium, which suffers loss of N2 to provide cation 16. Carbocation 16 then undergoes rearrangement to provide 3, which traps a nucleophile (typically water sometimes nucleophilic co-solvents or acid counterions like acetate) and provides the alcohol 4. 

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