PREPARATION AND SOME SUBSEQUENT TRANSFORMATIONS OF TETRAETHYNYLMETHANE

Tetraethynylmethane (1) was synthesized in 10 steps and 33% overall yield from bis[(trimethysilyl)ethynyl] ketone. This route features (1) construction of the critical central quaternary center via the agency of a [3,3] sigmatropic shift and (2) installation of the fourth acetylene unit in a very sterically demanding environment. Alternative routes and model systems which were more informative than productive are also discussed. Finally, transition metal-mediated coupling of the rather unstable 1 (and derivatives) with unsaturated partners furnished a variety of relatively stable polylalkynylated species which could be manipulated without event.