反应详情

Hydrazine hydrate and hydrogen peroxide (30 wt. % solution in water) were purchased from Mallinckrodt (Chesterfield, Mo.) and Fisher Chemical Co. (Fair Lawn, N.J.), respectively. Butyllithium (1.6M and 2.5M solutions in hexane), 2-(3-butynyloxy)tetrahydro-2H-pyran (1-(tetrahydopyran-2-yloxy)-3-butyne), lithium tetrahydridoaluminate, borane-methylsulfide complex, Cu(I)Br.Me2S complex, and p-toluenesulfonyl chloride from Aldrich Chemical Co. (Milwaukee, Wis.), and bromine and triphenylphosphine from Fluka Chemical Co. (Ronkonkoma, N.Y.), were used as purchased. 1-(Tetrahydopyran-2-yloxy)-4-pentyne was prepared from the corresponding alcohol using the methods described in Robertson, "Adducts of tert-alcohols containing an ethynyl group with dihydropyran. Potentially useful intermediates," J. Org. Chem. 25:931-932 (1960), the disclosure of which is hereby incorporated by reference. Column chromatography was run on silica gel (Merck, H 60), and reactions were monitored by TLC on Baker-flex Silica gel IB2-F plates (J. T. Baker). Silver nitrate column chromatography was done on silica gel impregnated with AgNO3 (20% of AgNO3 on silica gel Merck H 60).