Benzo-fused heterocycles, reduction

One of the themes to emerge from Bunce s research is the use of cascade reactions to produce an internal nucleophile that is subsequently intercepted by an enone to deliver heterocyclic architectures. Thus, nitro aromatics of type 387 undergo an iron-mediated reduction to furnish benzo-fused heterocycles 388 in 88-98% yield (Scheme 72) (OOJOC2847). Exposure of unsaturated esters like 389 to NaOEt... 

The reduction potentials of some pyrazines and their benzo-fused analogs have been summarized as part of an ESR study of the electron-transfer interaction between nitrogen heterocycles and -Bu4N BH4 <1995JOM(494)123>. 

A tautomeric equilibrium between enamine and methylene imine forms has been demonstrated to exist in 2-(3,4-dihydro-3-oxo-2(l//)-quinoxalinylidene)-Al-phenylacetamides and 3,4-dihydro-3-oxo-/V-phenyl-2-quinoxaline acetamides when these are in DMSO solution either in the absence or presence of TFA [95JHC671]. The reduction potentials of some pyrazines and their benzo-fused analogs have been summarized as part of an EPR study of the electron transfer interaction between nitrogen heterocycles and n-B N+BHf [95JOM123]. 

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