HERON reactions decomposition

Thermal decomposition reactions, of IV-acyloxy-lV-alkoxyamides, 90-96 free radical decomposition, 91-93 HERON reactions, 93-96 Thiazine dyes, 233... 

However, subsequent studies provided unequivocal evidence for consecutive three-centre rearrangements, the first step of which is a normal HERON reaction. Independent studies of decomposition of unsymmetrical hydrazines (227a and 227b) produced esters... 

HERON reactions in base-cataiysed decomposition of azodicarboxyiates... 

The reaction of iV-acyloxy-iV-alkoxyamides and aromatic amines, the thermal decomposition of iV,iV -diacyl-iV,iV -dialkoxyhydrazines as well as the base-induced decomposition of azodicarboxyiates are examples of the HERON reaction, one of the newest-named reactions in the chemical literature , but one that seems to be common for these as well as a range of other bisheteroatom-substituted amides . No doubt new examples will be discovered and it is entirely predicated upon the configurational and conformational properties of anomeric amides, attributes arising directly as a consequence of the dual electron demands of the heteroatoms at nitrogen. 

The formation of anhydrides 101 in the thermal decomposition reactions of TV-acyloxy-TV-alkoxyamides in non-polar mesitylene (Scheme 21, pathway (ii)) can thus be attributed to HERON migration of acyloxyl groups. However, the similarity of Eas for the two isomeric transition states raises the possibility that in these reactions some, or all of the ester might be generated by HERON migration of the alkoxyl substituent (Scheme 21, pathway (iii)). 

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