Smmry: Photolysis of [($ C, H,) Cr (CO),](1) and RG CR (2a, R= Ph; 2b, R= Tol) in toluene or n-hexane resutts in the formation of [(772: r14-CsH6R2) cr (cO)~](3a, b) in 70-85% isolated yield via a [6 4-21 cycloaddition reaction. Heating 3a, b in toluene gives the bicyclo [4.2. 1]- nona-2, 4, 7-trienes 4a, b and [(~-C, H, Me) Cr (CO),]. Photolysis of 1 and excess DMAD (dimethyl acetylenedicarboxylate, 5) in toluene at 0 OC yields the bicyclotriene 4c as the ...
[Mach, Karel; Antropiusova, Helena; Sedmera, Petr; Hanus, Vladimir; Turecek, Frantisek Journal of the Chemical Society, Chemical Communications, 1983 , # 15 p. 805 - 806]