Reaction Steps
Prepared from 2-(2-tert-butyldimethylsiloxyethyl)-3,4-dihydro-6-methoxy-3-oxo-2H-1,4-benzoxazine by methods F and G, alkylating with 3-chlorobenzyl bromide, in 80% overall yield. Isolated by crystallization from EtOH/water to afford a white powder, MS (Cl) 348 (MH+); IR (KBr) 3501, 3053, 3021, 2959, 2933, 2876, 2838, 1664, 1618, 1600, 1575, 1512, 1466, 1445, 1435, 1390, 1361, 1337, 1313, 1272, 1237, 1201, 1173, 1107, 1078, 1049, 1030 cm-1 ; 1H NMR (CDCl3) δ 7.27-7.20 (m, 3H), 7.13 (m, 1H), 6.94 (d, J=8.8 Hz, 1H), 6.52 (dd, J=9.1, 2.7 Hz, 1H), 6.41 (d, J=2.7 Hz, 1H), 5.12 (d, J=16.2 Hz, 1H), 4.79 (dd, J=8.2, 5.4 Hz, 1H), 3.92 (m, 2H), 3.68 (s, 3H), 3.39-2.16 (m, 2H), 2.17 (t, J=5.9 Hz, 1H). Anal. Calc'd for C18H18ClNO4.0.25 H2O: C 61.37, H 5.29, N 3.98. Found: C 61.35, H 5.14, N 3.95.
