The N-heterocyclic carbene (NHC)-catalyzed formal [2 + 2] cycloaddition between α-aroyloxyaldehydes and trifluoroacetophenones, followed by ring opening with an amine or a reducing agent is described. The resulting β-trifluoromethyl-β-hydroxyamide and alcohol products are produced with reasonable diastereocontrol (typically ≈70:30 dr) and excellent enantioselectivity, and they can be isolated in moderate to good yield as a single diastereoisomer.

中文翻译：

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NHC催化的β-三氟甲基-β-羟酰胺的对映选择性合成。

描述了在α-芳酰氧基醛和三氟苯乙酮之间进行N-杂环卡宾（NHC）催化的甲醛[2 + 2]环加成反应，然后用胺或还原剂进行开环。生成的β-三氟甲基-β-羟基酰胺和醇产物具有合理的非对映异构控制（通常≈70:30 dr）和出色的对映选择性，可以作为单一非对映异构体以中等至良好的收率分离。