benzyl 2-(oxetan-3-ylidene)acetate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of N-methyl-propargylamine (0.27 g) and benzyl 2-(oxetan-3-ylidene)acetate (0.41 g) was stirred neat at RT for 12 h. The excess amine was removed by evaporation to give benzyl 2-(3-(methyl(prop-2-ynyl)amino)oxetan-3-yl)acetate quantitatively (0.54 g). The excess amine was removed by evaporation

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Under argon and at room temperature, 1.6 ml (2.37 mmol) of a 1.5 M aqueous potassium hydroxide solution, 272 mg (1.82 mmol) of benzyl oxetan-3-ylideneacetate and 750 mg (1.82 mmol) of {3-[bis(4-methoxybenzyl)amino]-4-chlorophenyl}boronic acid were added successively to a solution of 45 mg (0.09 mmol) of (1Z,5Z)-cycloocta-1,5-diene/rhodium(I) chloride dimer in 25 ml of dioxane. The reaction solution was then stirred at room temperature for 4 h. After the reaction had gone to completion, the solution was concentrated to dryness and the residue was taken up in 25 ml of water and 25 ml of ethyl acetate. The phases were separated and the aqueous phase was extracted three more times with ethyl acetate, and the combined organic phases were dried over magnesium sulphate and concentrated to dryness. The crude product obtained was purified chromatographically on silica gel (mobile phase cyclohexane/ethyl acetate 4:1→1:1). This gave 669 mg (1.17 mmol, 64% of theory) of the title compound. the solution was concentrated to dryness The phases were separated the aqueous phase was extracted three more times with ethyl acetate the combined organic phases were dried over magnesium sulphate concentrated to dryness

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Under argon and at 0° C., 3.0 g (41.63 mmol) of oxetan-3-one (CAS Reg.-No. 6704-31-0) were dissolved in 50 ml of dichloromethane, and 18.8 g (45.79 mmol) of benzyl (triphenyl-λ5-phosphanylidene)acetate were then added. The reaction mixture was then slowly warmed to room temperature and stirred for another 15 minutes. The reaction solution was then concentrated to dryness. The residue was taken up in 25 ml of diethyl ether and stirred, and the mixture was kept at 4° C. for 12 h. The precipitated triphenylphosphine oxide was filtered off and the filtrate was concentrated to dryness. The crude product obtained was purified chromatographically on silica gel (mobile phase cyclohexane/ethyl acetate 4:1→1:1). This gave 4.2 g (20.57 mmol, 49% of theory) of the title compound. The reaction solution was then concentrated to dryness stirred the mixture was kept at 4° C. for 12 h The precipitated triphenylphosphine oxide was filtered off the filtrate was concentrated to dryness