A convenient synthetic entry into 2,2-diorganyl-5,6-diaryl-1,3,4,2-dioxazasilacyclohexene derivatives via dianion cyclisation: Sequential one-pot cyclosylation.

In a convenient one-pot sequence, treatment of bezoin and p-anisoin oximes with sodium hydride in dry THF in 1.2 molar ratio generates 1,5-dianion, wh ich upon subsequent addition of diorganodichlorosilane yields 1,3,4,2-dioxa zasilacyclohexene derivatives in good yields. In general, very often a salt elimination route is used for the synthesis of the title compounds.