L. Crombie et al., REACTIONS BETWEEN (E)-5,5'-DIMESITYLBIFURANYLIDENEDIONE AND THE HORNER-WITTIG REAGENT, Tetrahedron letters, 37(51), 1996, pp. 9255-9258
(E)-5,5'-Dimesitylbifuranylidenedione 1 reacts with the Horner - Witti
g reagent by attack at one carbonyl giving 3; subsequent Michael addit
ion of a second molecule of ylide leads to 4 by dehydrogenation, whils
t 9 is a dimeric product. Copyright (C) 1996 Elsevier Science Ltd