Using an Aldehydo Amide, Nitrile, Acyl Halide, or Related Synthon

Using an Aldehydo Amide, Nitrile, Acyl Halide, or Related Synthon 

Each such category of synthon has potential for the synthesis of quinoxalines or hydroquinoxalines, but very few examples have been reported. 

2-Benzenediamine (148) and frani-l-chloro-l,2-bis(hydroxyimino)ethane (149) gave 2(177)-quinoxalinone oxime (150), perhaps better formulated as 2-hydroxyaminoquinoxaline (151) (EtOH, 20°C, 3 h 71%) 6,7-dibromo-l,2-benzenediamine likewise gave 6,7-dibromo-2-hydroxyamino-quinoxaline.  

4-Nitro-l,2-benzenediamine (152) and chloroacetonitrile (153) gave 6-nitro-3,4-dihydro-2-quinoxalinamine (154), apparently without 7-nitro isomer (Et3N, p-xylene, reflux, 6 h 47%).  

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