Tetrahedron Letters,Vol.28,No.29,pp 3373-3376,1987 0040-4039/87 $3.00 + .OO ... RING CLEAVAGE AND RECONSTRUCTION OF FIVE AND SIX MEMBERED RING ... Hiroshi Suemune, Kozo Oda and Kiyoshi Sakai Faculty of Pharmaceutical Sciences, Kyushu University, 3-ll Maidashi, Higashi-ku, Fukuoka 812, Japan ... Summary: glycol, Under the acetalization conditions using BF3-etherate/ethylene cyclopentanones and cyclohexanones with the carbonyl ...