Chiral ruthenium complexes as catalysts in enantioselective Diels–Alder reactions. Crystal structure of the Lewis acid–dienophile adduct

Abstract

On the basis of spectroscopic and structural studies a full catalytic cycle is proposed for the Diels–Alder reaction between methacrolein and cyclopentadiene when the new chiral aquo-complexes (R_Ru, S_Ru)-[(η⁶-p-cymene)Ru(PN)(H₂O)][SbF₆]₂ {PN = (3aS, 8aR)-2-(2-diphenylphosphinophenyl)-3a,8a-dihydroindane[1,2-d]oxazole} are used as catalysts.

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