Phosphine-Catalyzed Difunctionalization of β-Fluoroalkyl α,β-Enones: A Direct Approach to β-Amino α-Diazo Carbonyl Compounds.
Huamin WangLi ZhangYoushao TuRuiqi XiangYin-Long GuoJunliang ZhangPublished in: Angewandte Chemie (International ed. in English) (2018)
An efficient and practical phosphine-catalyzed vicinal difunctionalization of β-fluoroalkyl α,β-enones with TMSN3 has been developed. Using dppb as the catalyst, the reaction worked efficiently to yield various β-amino α-diazocarbonyl compounds in high yields (up to 94 %). This work marks the first efficient construction of α-diazocarbonyl compounds by phosphine catalysis. Meanwhile, the asymmetric variant induced by the nucleophilic bifunctional phosphine P4 led to various chiral fluoroalkylated β-amino α-diazocarbonyl compounds in high yields and enantioselectivity. NMR and ESI-MS studies support the existence of the key reaction intermediates. In contrast, β-azide carbonyl compounds would be furnished in good yields from β-fluoroalkylated β,β-disubstituted enones.