Example 1 (a) Synthesis of benzyloxyacetyl chloride: to a solution of dichloromethane (50 mL) containing benzyloxyacetic acid (10.0 g, 60.0 mmol, 8.6 mL) was sequentially added oxalyl chloride (9.1 g, 72.0 mmol, 6.0 mL) and N,N-dimethylformamide (DMF, 30.0 mg, 0.4 mmol, 32.0 μL). The reaction mixture was stirred for 3 h at room temperature. Rapid gas release was observed at the beginning of the reaction, which gradually stopped as the reaction progressed. Upon completion of the reaction, the dichloromethane solution was concentrated under reduced pressure to give a colloidal product. Subsequently, additional oxalyl chloride (4.5 g, 35.7 mmol, 3.0 mL), dichloromethane (50 mL), and a drop of DMF were added to the gelatinous product, and the reaction mixture was again stirred for 2 h, during which a rapid gas release was observed. Finally, the reaction mixture was concentrated under reduced pressure to afford benzyloxyacetyl chloride (1) 11.0 g (in quantitative yield) as a gel. The structure of the product was confirmed by 13C NMR (75 MHz, CDCl3) with chemical shifts of δ 73.6, 74.8, 128.1, 128.4, 128.6, 130.0 and 171.9.
