One-pot synthesis of CpRe(CO)2H2 and trans-CpRe(CO)2(SnPh3)2 from cis- and trans-CpRe(CO)2Br2 and Ph3SnH. Involvement of a radical-chain sequence in the formation of CpRe(CO)2H2 - Simon Bott (Inorganica Chimica Acta, 1995)