Bidentate carbenoid ester coordination in non-planar ruthenium(II) complexes leading to excellent levels of both diastereo- and enantioselectivity in catalytic alkene cyclopropanation

General experimental details. All organometallic and catalytic procedures were carried out under an inert atmosphere of argon by using a dual manifold vacuum/argon line and standard schlenk techniques, or in an MBraun glove box. All solvents were predried by refluxing for three days under dinitrogen over the appropriate drying agents (sodium for toluene; potassium for THF; sodium-potassium alloy for diethyl ether, petroleum ether and pentane; calcium hydride for dichloromethane, pyridine and acetonitrile) and degassed before use. Solvents were stored in glass ampoules under argon. All glassware, cannulae and Celite were stored in an oven (>100C) and flame dried immediately prior to use. Most reagents and chemicals were purchased from Aldrich Chemical Company and used without further purification. Deuterated solvents were freeze-thaw-degassed and dried by refluxing over potassium (or calcium hydride for CD2Cl2) before being vacuum distilled to a clean, dry Young's tap ampoule and being stored in the glove box. Deuterated chloroform was dried over molecular sieves (4Å) in the air.