Table 2.
Temperature dependence on the regioselectivity (2/3) and the yields in the Paternò–Büchi reactions of DMT with compounds 1b–ea.
| Temp./°C | 2/3 (yield %) | |||
| 1b | 1c | 1d | 1e | |
| −27.4 | 70:30 (63.9) | 73:27 (62.2) | 54:46 (75.6) | 50:50 (37.6) |
| −21.4 | 68:32 (61.1) | 70:30 (58.4) | 52:48 (68.5) | 46:54 (37.5) |
| −11.5 | 64:36 (62.5) | 67:33 (62.3) | 46:54 (69.6) | 40:50 (44.4) |
| −0.9 | 61:39 (51.0) | 62:38 (52.5) | 42:58 (74.7) | 36:64 (38.3) |
| 9.9 | 56:44 (46.9) | 58:42 (49.7) | 39:61 (75.0) | 31:69 (38.5) |
| 20.1 | 52:48 (44.0) | 56:44 (47.4) | 34:66 (74.4) | 30:70 (32.8) |
| 30.0 | 48:52 (43.1) | 51:49 (45.9) | 30:70 (63.4) | 25:75 (29.2) |
| 40.0 | 41:59 (36.3) | 41:59 (43.0) | 26:74 (67.4) | 23:77 (26.7) |
| 49.5 | 37:63 (32.2) | 35:65 (43.8) | 21:79 (62.8) | 18:82 (22.4) |
| 60.0 | 31:69 (24.1) | 29:71 (43.5) | 17:83 (63.5) | 14:86 (14.5) |
| 69.1 | 27:73 (25.8) | 25:75 (41.3) | 14:86 (59.8) | 10:90 (11.4) |
aSee Table 1.