H-Bonding as a Control Element in Stereoselective Ru-Catalyzed Olefin Metathesis

H-bonding interactions have been exploited extensively in the design of catalysts for stereoselective synthesis but have rarely been utilized in the development of metal-catalyzed processes. Studies described herein demonstrate that intramolecular H-bonding interactions can significantly increase the rate and levels of stereochemical control in Ru-catalyzed olefin metathesis reactions. The utility of H-bonding in catalytic olefin metathesis is elucidated through development of exceptionally facile and highly diastereosetective ring-opening/cross-metathesis (DROCM) reactions, involving achiral Ru catalysts and enantiomerically enriched allylic alcohols. Transformations proceed to completion readily (>98% conversion, up to 87% yield), often within minutes, in the presence of <= 2 mol % of an achiral catalyst to afford synthetically versatile products of high stereochemical purity (up to >98:2 dr and 11:1 E:Z).