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3106375 
Journal Article 
REGIOSELECTIVE CLEAVAGE REACTION OF THE AROMATIC METHYLENEDIOXY RING .5. CLEAVAGE WITH SODIUM ALKOXIDES ALCOHOLS, POTASSIUM TERT-BUTOXIDE ALCOHOLS, DIMSYL ANION METHYL-ALCOHOL, METALLIC SODIUM ALCOHOLS, AND SODIUM-CYANIDE IN DIPOLAR APROTIC-SOLVENTS 
Imakura, Y; Okimoto, K; Konishi, T; Hisazumi, M; Yamazaki, J; Kobayashi, S; Yamashita, S 
1992 
Yes 
Chemical and Pharmaceutical Bulletin
ISSN: 0009-2363
EISSN: 1347-5223 
40 
7 
1691-1696 
WOS:A1992JH01600003 
The reaction of aromatic methylenedioxy compounds containing electron-withdrawing groups with dimsyl anion-methyl alcohol, potassium tert-butoxide-alcohols, and metallic sodium-alcohols in dimethyl sulfoxide (DMSO), and with sodium alkoxides-alcohols in hexamethylphosphoramide, gave 3- and 4-hydroxybenzene derivatives in good yield by regioselective attack of the alkoxide ions on the methylenedioxy ring. The formation mechanism of alkoxide ions and the effect of DMSO in the cleavage reaction of the methylenedioxy ring are discussed on the basis of proton nuclear magnetic resonance (H-1-NMR) spectra. The reactions of aromatic methylenedioxy compounds (3 and 22) with sodium cyanide in dipolar aprotic solvents gave 4-cyano-3-hydroxybenzene derivatives (23 and 24) by regioselective attack of the cyanide ion on the methylenedioxy ring. The reactions of aromatic methylenedioxy compounds (28-30) containing no electron-withdrawing group with MeONa-MeOH in dipolar aprotic solvents gave non-regioselective cleavage products 31 and 34). 
REGIOSELECTIVE CLEAVAGE REACTION; METHYLENEDIOXY RING; SODIUM ALKOXIDE; DIMSYL ANION; POTASSIUM TERT-BUTOXIDE; ELECTRON-WITHDRAWING GROUP; CYANIDE ION; DIPOLAR APROTIC SOLVENT