CAS RN: 90965-06-3 | 產品號碼: D3546
|Appearance||Light yellow to Brown clear liquid|
|Purity(HPLC)||min. 97.0 area%|
Synthesis of Phosphonyl Pyrazoles
Typical Procedure: To a stirred solution of aldehyde (1 mmol), cyanoacid derivative (1.2 mmol) and Ohira-Bestmann reagent (1.5 mmol) in distilled MeOH (4 mL), is added molecular sieves followed by powdered KOH (2 mmol). The reaction mixture is stirred at room temperature for one hour. After the completion of the reaction (TLC monitoring), methanol is distilled off under reduced pressure. The crude residue is dissolved in ethyl acetate (50 mL) and washed with saturated ammonium chloride (2×20 mL). Finally the organic layer is washed with saturated brine (20 mL) and dried over anhydrous sodium sulphate. After removal of the solvent, column chromatographic purification is carried out using acetone-dichloromethane as eluent to afford the products.
- K. Mohanan, A. R. Martin, L. Toupet, M. Smietana, J.-J. Vasseur, Angew. Chem. Int. Ed. 2010, 49, 3196.
One-pot Synthesis of Terminal Alkynes
- S. Ohira, Synth. Commun. 1989, 19, 561.
- S. Muller, B. Liepold, G. J. Roth, H. J. Bestmann, Synlett 1996, 521.
- H. D. Dickson, S. C. Smith, K. W. Hinkle, Tetrahedron Lett. 2004, 45, 5597.
- E. Quesada, R. J. K. Taylor, Tetrahedron Lett. 2005, 46, 6473.