Table 1.
Entry | RCHO | R = | HWE (% Yield) | Stilbene | Hydrolysis (% Yield) | Schwein. | R = |
---|---|---|---|---|---|---|---|
1 | 13 | H | 66% | 43 | 53% | 51 | H |
2 | 18 a | Br | 54% | 44 a | 92% | 52 | Br |
3 | 25 | F | 53% | 45 | 77% | 53 | F |
4 | 31 | SCH3 | 74% | 46 | 40% | 54 | SCH3 |
5 | 40 | CH2OCH3 | 50% | 47 | 41% | 55 | CH2OCH3 |
6 | 41 | OMOM | 77% | 48 | 61% | 56 | OH |
7 | 42 | OCH3 | 90% | 49 | 92% | 57 | OCH3 |
8 | 34 | CH2OTBS | 36% | 50 |
In this series, the aldehyde and stilbene bear a C-2 MOM group that is cleaved in the final hydrolysis.