A Single-Flask Synthesis of Morita-Baylis-Hillman Adducts from Ethoxyacetylene and Carbonyl Compounds: Synthesis of Subamolides D and E

作者：Ng Kevin; Minehan Thomas G^*

来源：Organic Letters, 2016, 18(16): 4028-4031.

DOI：10.1021/acs.orglett.6b01772

Sequential treatment of (ethoxyethynyl)lithium with aldehydes and/or ketones (2 and 4) and BF3 center dot OEt2 gives rise to beta-hydroxyenoates 5 in good to excellent overall yields. Similarly, the combination of 1 (M = Li) and dicarbonyl compounds 6 (X = 0) or keto/aldehyde acetals (X = OMe) followed by the addition of a Lewis acid leads to five-, six-, and seven-membered hydroxycycloalkene carboxyates. The utility of this method is demonstrated in the synthesis of the alpha-alkylidene lactone natural products subamolide D and E.

• 出版日期2016-8-19