Mild and robust Stille reactions in water using ppm levels of a new triphenylphosphine-based palladacycle.

An inexpensive and new triphenylphosphine-based palladacycle has been developed as a pre-catalyst leading to highly effective Stille cross coupling reactions in water under mild conditions. Only 500-1000 ppm of Pd suffices for couplings involving a variety of aryl/heteroaryl halides with aryl/hetaryl stannanes. Several drug intermediates can be prepared using this catalyst in aqueous nanoreactors formed by 2 wt % Brij-30 in water.