“…65 (m, 1H), 1.50 (dd, J = 5.2, 13.9, 1H), 1.30 (t, J = 7.1, 3H), 1.29 (t, J = 7.1, 3H), 1.16 (s, 3H), 0.93 (d, J = 6.6, 3H), 0.85 (t, J = 6.6, 3H). 13 (s, 3H). 13 (R)-diethyl 3-hydroxy-2, 2-dipropylsuccinate (4h) and (R)-diethyl 2, 2-diallyl-3-hydroxysuccinate (4i) were difficult to purify from the reaction mixture because their Rf was very close to that of the starting materials (3h and 3i respectively).…”