NMR AND AML QUANTUM-CHEMICAL STUDY OF THE REGIOSELECTIVITY OF THE REACTION OF 2-HYDROXYETHYL METHACRYLATE WITH 3-NITROPHTHALIC ANHYDRIDE

The reaction of 2-hydroxyethyl methacrylate with 3-nitrophthalic anhyd ride catalyzed with triethylamine results in the 3:1 mixture of two po ssible monoesters, the more populated one being that with the ester gr oup in ortho position to the nitro group. The isomers were identified and quantified by H-1 and C-13 1D and 2D techniques including APT, INE PT, superselective long-range (SSLR) INEPT, SSLR HHCR, COSY, NOESY, HE TCOR and COLOC. Theoretical analysis was done on the model reaction of methanol with the anhydride using semiempirical AM1 quantum chemical calculations. The results indicate that the relative regioselectivity of the reaction is due to both the electron distribution in the anhydr ide molecule and hydrogen bonding in the stages immediately preceding the transition state.