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DOI: 10.1055/sos-SD-047-00100

Petasis, N. A.Science of Synthesis, (201047181.

The methylenation of aldehydes with the Petasis reagent 37 is generally a synthetically useful process (Table 8).[‌60‌,‌73‌‌77‌] 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]

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