BROMINATION OF DECALIN AND ITS DERIVATIVES .9. HIGH-TEMPERATURE BROMINATION

Thermal and photobromination of decalin, 1, was studied, trans,cis,tra ns-2,5,7,9-tetrabromooctalin 2, was obtained as the major product alon g with smaller amounts of bromonaphthalene derivatives. The structures of the products were determined by H-1- and C-13-NMR data and single X-ray structural analysis. Bromination of the two decalin derivatives 9 and 10 results in the formation of single isomers 11 and 12, respect ively. The three tetrabromides 2, 11, and 12 were shown by molecular m echanics calculations to be the most stable stereoisomer in each case. The formation of these tetrabromides under thermodynamic control is p ostulated.