Mercuricyclisation of D-erythro-hept-1,3-dienitol: Reductive demercuriation in the presence and absence of oxygen

Abstract

Treatment of 3,5,7-tri-O-benzyl-D-erythro-hept-1,3-dienitol with mercuric acetate or trifluoromethanesulfonate followed by aqueous potassium chloride, produced (1,3,5-tri-O-benzyl-2-deoxy-2-chloromercurio-β-D- arabinofuranosyl)ethene (2) as the only isolated product. Reductive demercuriation of the chloromercurio-ether 2 in the presence of molecular oxygen gave a mixture of 3,7-dibenzyloxy-hept-1,3,5-triene-6-ol (3), (1,3,5- tri-O-benzyl-β-D-arabinofuranosyl)ethene (4) and D-ribofuranosyl)ethene (5). Compound 3 was obtained as the major product when the reaction was conducted at room temperature. At 0 °C, the reaction gave a 3:1 mixture of 4 and 5, with 3 being formed in only minor amounts.