“…The sulfoxide was prepared using general procedure A for the synthesis of sulfoxides: pale yellow solid (0.38 g, 67%), which was used without further purification: mp 84–85 °C (lit . 85–88 °C); ν max (neat)/cm –1 1715 (CO); δ H (400 MHz) 2.26–2.36 (1H, m, one of C H 2 ), 2.51–2.64 (2H, m, C H 2 ), 2.78–2.94 (1H, m, one of C H 2 ), 2.95–3.05 (1H, m, one of C H 2 ), 3.08–3.16 (1H, m, one of C H 2 ), 3.63 (1H, A of AB q , J 13.3, one of C H 2 ), 3.69 (1H, B of AB q , J 13.3, one of C H 2 ); δ C (75.5 MHz) 19.3, 41.4, 46.7, 59.8, 199.7; m / z (ESI+) 133 [(M + H) + , 30)].…”