Stannylation of unsaturated carbon–carbon bonds by tin tetrachloride

The effect of the oxidation state of molybdenum complexes on the catalytic transformation of terminal alkynes: Cyclotrimerization vs. polymerization

“…The in situ generated coordinatively unsaturated molybdenum(II) species interacts with alkynes to give a bisalkyne complex which can be transformed in the presence of an excess of alkyne to give cyclotrimers. However, at a molar ratio of SnCl 4 /2 higher than 2, the simultaneous formation of the recently described stannylation product of alkyne by SnCl 4 (chlorovinyltin trichlorides) (Scheme 4) [50] was observed. Thus, tin tetrachloride reacts with the molybdenum(0) complex 2 as well as with alkynes.…”