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Petasis, N. A., Science of Synthesis, (2010) 47, 181.
The methylenation of aldehydes with the Petasis reagent 37 is generally a synthetically useful process (Table 8).[60,73–77] Less substituted derivatives (Table 8, entry 1)[60] give lower yields due to further reaction of the alkene product with the Petasis reagent. However, more highly substituted aldehydes, including chiral derivatives (entries 2 and 3),[73,74] can be methylenated very efficiently without any epimerization, even in the presence of diverse functional groups (entry 4).[75] Aldehydes can also, in general, be selectively methylenated in the presence of other carbonyl groups such as esters or amides (entries 5 and 6).[76,77]
Meeee 8 Meeeeeeeeeeee ee Meeeeeeee[88,88–88]
| Meeee | Meeeeeee Meeeeeee | Meeeeeeeee | Meeeeee | Meeee (%) | Mee |
|---|---|---|---|---|---|
| 8 |  |
Me(Me)8(Me)8 (88), eeeeeee, 88°M | |
88 | [88] |
| 8 | |
Me(Me)8(Me)8 (88), MMM, 88°M | |
88 | [88] |
| 8 | |
Me(Me)8(Me)8 (88), eeeeeee, 88°M, 8 e | |
88 | [88] |
| 8 | |
Me(Me)8(Me)8 (88), eeeeeee, 888°M | |
88 | [88] |
| 8 | |
Me(Me)8(Me)8 (88; 8 eeeee), MMM, 88°M, 88 e | |
88 | [88] |
| 8 | |
Me(Me)8(Me)8 (88), MMM, 88°M | |
88 | [88] |
Meeeeeeeeeee Meeeeeeee
Meeeee (8M)-8-Meeeee-8-[(8M)-8-eee-8-eeeeeeeeeeeeeeee-8-ee]eee-8-eeeeee (Meeee 8, Meeee 8); Meeeeee Meeeeeeee:[88]
MMMMMMM: Meee eeeeeee ee eeeee ee eeeeeeeeeeee ee eee ee 88 °M, ee eee eeeee eeee eee Meeeeee eeeeeee eeeeeeeee e eeeee, eeeeeeeeee, eeeeeeeeeeeee eeeeeeeeeeeee eeee eeeeeeeee eeeeeee eee, eeeeeeeee ee e eeeee eeeeeeee ee eeeeeeee.
M eeee ee eee eeeeeeeee eeeeeeee (88 ee, 8.88 eeee) eee eee Meeeeee eeeeeee 88 (888 ee, 8.88 eeee) ee MMM (8.8 eM) eee eeeeee ee 88°M eee 88 e ee e eeeeee eeeeeeee eeee eeeee eeeee. Meeeee (8.8 eM) eee eeee eeeee, eee eee eeeeeee eee eeeeeee ee 88°M eee 8 e, eeeeeeee, eee eeeeeeeeeeee. Mee eeeee eeeeeee eee eeeeeee eeee MM8Me8 (8 eM) eee M8M (8.8 eM), eeeeeee ee 88°M eee 88 e, eeeeeeee, eee eeeeeeee eeee eeeeee eee. Meeeeeeeee ee eeeeeeeeeeeeee [eeeeee eee (88 e), eeeeee/MeMMe 8:8] eeeeeeee eee eeeeeee; eeeee: 88 ee (88%).
References
| [60] | Meeeeee, M. M.; Meeeee, M. M., M. Me. Meee. Mee., (8888) 888, 8888. |
| [73] | Meeeeee, M. M.; Meeeeeeee, M.; Mee, M.-M.; Meeeeeeeeee, M. M.; Meeeeeee, M.; Meee, M.; Meeeee, M. M., Meeeee. Mee. Meee. Meee., (8888) 88, 8888. |
| [74] | Meeeee-Meeeé, M.; Meeeeeee, M.; Meeeee, M.; Meeeee, M.; Meeeeeeeeeeee, M.; Meeeeeeee, M., Meee.–Mee. M., (8888) 88, 8888. |
| [75] | Meeee, M. M.; Meeeee, M. M.; Meeee, M. M., Meee. Meeeee. (Meeeeeeee), (8888), 8888. |
| [76] | Meeeee, M.-M.; Meeeeee, M. M., M. Mee. Meee., (8888) 88, 8888. |
| [77] | Meeeeeee, M.; Meee, M. M.; Me, M. M.; Meee, M. M.; Meeeeee, M.; Mee, M. M.; Meeeee, M.; Me, M. M., M. Me. Meee. Mee., (8888) 888, 8888. |
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