2.2.3.3.5.6- Hexamethyl-2,3-dihydropyrazine 1,4-dioxide

Reduction of 2,2,3,3,5,6-hexamethyl-2,3-dihydropyrazine 1,4-dioxide (78) with sodium borohydride gave l,4-dihydroxy-2,2,3,3,5,6-hexamethylpiperazine (555) and attempted deoxygenation of (78) by zinc and hydrochloric acid gave the bishydroxylamine (79) (555). Compound (78) did not form benzylidene derivatives with benzaldehyde (555) and it was only slowly attacked by selenium dioxide one equivalent of selenium dioxide required 5 days boiling under reflux before the nitrone was completely reacted, and the product was thought to be 6-formyl-... 

Although hexamethyl-2,3-dihydropyrazine 1,4-dioxide (166) does not exhibit typical nitrone properties, oxaziridines are nevertheless formed on photolysis with light of wavelength greater than 300 nm, only the monooxaziridine (167) is formed, whereas with light of wavelength down to 200 nm, cis- (168) and trans- (169) dioxaziridines are obtained.148... 

The photochemical isomerization of hexamethyl-2,3-dihydropyrazine 1,4-dioxide has been investigated (1606). 

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