Catalytic tin radical mediated tricyclisations. Part 2For Part 1, see ref. 5.The full experimental and spectroscopic data for D-series compounds are available as supplementary data. For direct electronic access see http://www.rsc.org/suppdata/p1/b0/b000662i/ (this includes the following compounds in order of appearance: 15a, 15b, 16, 17a, 18a, 17b, 18b, 24b, 24c, 24d, 24e, 25, 26, 27a, 28a, 46a, 46b, 48, 49a, 49b and tabular data for 43, 53a, 53b).

Propenyl 4-O-propargyl-, propargyl 4-O-propenyl-, and propargyl 4-O-propargyl-2,3-dideoxy-α-D-erythro-hex-2-enopyranosides undergo catalytic, tin radical initiated, cascade reactions, in which three rings are constructed in a single reaction. In each case, a lack of stereoselectivity in the second cyclisation results in an additional product which is produced non-catalytically. The dienes which result from catalytic cyclisation of propargyl 4-O-propargyl-2,3-dideoxy-α-D-erythro-hex-2-enopyranosides, undergo in situ hydrostannylation to give unusual allylstannanes.