Synthetic applications of bis(iminophosphoranes). One-pot preparation of rigid bicyclic guanidines
摘要:
A one-pot synthesis of [6 + 6], [6 + 7], and [6 + 8] bicyclic guanidines based on a new method of dihydropyrimido annelation, which involves reaction of bis(iminophosphoranes) with aryl isocyanates or isothiocyanates is described. The method is also applicable for the preparation of chiral bicyclic guanidines.
The Staudinger reaction between bis(azides) and bis(phosphines) under mild conditions provides macrocyclic bis(iminophosphoranes) (at least 12-membered rings) in excellent to moderate yield. The method also allows the incorporation of a heteroatom into the chain connecting the two aromatic or heteroaromatic rings.
Tripod-Tripod Coupling of Triazides with Triphosphanes. The Synthesis, Characterization, and Stability in Solution of New Cage Compounds: Chiral Macrobicyclic Triphosphazides