ADDITION AND CYCLIZATION REACTIONS IN THE THERMAL CONVERSION OF HYDROCARBONS WITH AN ENYNE STRUCTURE, 7. - CYCLOISOMERIZATION OF 1-PHENYL-1-BUTEN-3-YN E TO NAPHTHALENE VIA CINNAMYLIDENE CARBENES : A COMPLEX REACTION INVOLVING 1,2-C SWITCHES AND 1,2-STYRYL MIGRATIONS