N. Launay et al., SYNTHESIS AND MACROCYCLIZATION OF SOME BIS[FORMYL (ARYL OR HETEROARYL)]SILANES, Bulletin de la Societe chimique de France, 131(7), 1994, pp. 758-762
The reactions of the new bis(5-formyl-2-heteroaryl)dimethylsilanes 5,
6, and bis(3-formylphenyl)dimethylsilane 13, obtained from the corresp
onding acetals, with phosphono-dihydrazides PhP(X)[(N(CH3)NH2)]2 14 (X
= S) or 15 (X = 0) led quantitatively to the silicon- and phosphorus-
containing macrocycles 16-20 arising from selective [2 + 2] cycloconde
nsation reactions.