Acryloyl chloride (Acros)
Dichloromethane (distilled from calcium hydride)
N-Ethyldiisopropylamine (Lancaster)

To a stirring solution of the acryloyl chloride (47 uL, 0.578 mmol, 1.1 eq.) and N-ethyldiisopropylamine (0.1 mL , 0.578 mmol, 1.1 eq.) in dichloromethane (3 mL), was added a solution of the chiral auxiliary (0.1 g, 0.526 mmol, 1 eq.) and N-ethyldiisopropylamine (91 uL, 0.526 mmol, 1 eq.) in dichloromethane (5 mL) by cannula. The reaction was at room temperature and under nitrogen. The reaction mixture was stirred for 2 hours and quenched by adding saturated ammonium chloride solution(10 mL). Work up involved dilution with dichloromethane (10 mL) and the combined organic extracts were dried, filtered and the solvent removed to afford a yellow solid. A short column eluting with 10:1-0:1 PE:Et₂O gave the required product as a white solid (128 mg, 100 %).

We have coupled various acid chlorides to the imidazolidinone using 2,6-Lutidine, however in this particular case we were obtaining particularly disappointing yields (< 50 %). This procedure is from the literature where the group coupled an acryloyl chloride to a thiazolidine which is very similar to our system. However instead of quenching with water, I modifyied the protcol slightly by quenching with sat. NH₄Cl solution. This method has been carried out at both low to high scales ranging from 10 mg to 500 mg of the imidazolidinone.

¹H NMR (300 MHz, CDCl₃) 0.78 (3H, d, J 6.60, CCH₃) 2.83 (3H, s, NCH₃) 3.85-3.89 (1H, m, CHCH₃) 5.32 (1H, d, J 8.53, CHPh) 5.72 (1H, d, J 8.41, CHCH₂) 6.27 (1H, d, J 19.07, CHCH₂) 7.11-7.48 (5H, m, CH_ar)7.63-7.72 (1H, dd, CHCH₂)

N.A. Porter, I.J. Rosentein, R.A. Breyer, J.D. Bruhnke, W. Wu, A.T. McPhail; J. Am. Chem. Soc, 1992, 114 7664-7676.