Polycyclic dinitroxide radicals - nmr spin indicators

摘要

Title cpds. are of formula (I): (where R1 and R2 = alkyl, and A = a tetravalent org. radical to stabilise the nitroxide gps.). The radicals are prepd. by reaction of a ketone R1-CO-R2 with a diamine dihydroxy cpd. (HO)2-A-(NH2)2 (II), followed by oxidn.