Highly Diastereoselective Synthesis of Fully Substituted Tetrahydrofurans by a One-Pot Cascade Reaction of Aryldiazoacetates with Allyl Alcohols

A new one-pot cascade reaction for the construction of fully substituted tetrahydrofurans from aryldiazoacetates and allyl alcohols has been reported. This method provides an effective way to prepare fully anti-substituted tetrahydrofurans in a simple procedure. The relative stereochemistry of the product was determined to be all trans-aryl substituents by single-crystal X-ray analysis. The reaction mixture was stirred at 45°C, and a solution of the diazo compound 1 (0.20 mmol) in toluene (0.5 ml) was added to the reaction mixture over a period of 1 hour through a syringe pump. The one-pot cascade reaction afforded the desired product in 70% yield as a single enantiomer bearing four chiral stereogenic carbon centers without any loss of enantioselectivity. The current method highlighted a rhodium (II)-catalyzed, highly diastereoselective, 0-H insertion of aryldiazoacetate to a secondary ally alcohol, followed by a highly stereoselective intramolecular Michael- type addition.