Enantioselective, Catalytic Fluorolactonization Reactions with a Nucleophilic Fluoride Source

The enantioselective
synthesis of 4-fluoroisochromanones via chiral aryl iodide-catalyzed
fluorolactonization is reported. This methodology uses HF-pyridine
as a nucleophilic fluoride source with a peracid stoichiometric oxidant
and provides access to lactones containing fluorine-bearing stereogenic
centers in high enantio- and diastereoselectivity. The regioselectivity
observed in these lactonization reactions is complementary to that
obtained with established asymmetric electrophilic fluorination protocols.

本研究报道了通过手性芳基碘化物催化的氟代内酯化反应，实现4-氟异色满酮（4-fluoroisochromanones）的对映选择性合成。该方法采用氟化氢-吡啶（HF-pyridine）作为亲核氟源，以过酸作为化学计量氧化剂，可得到带有含氟手性中心的内酯类化合物，且具有优异的对映选择性与非对映选择性。此类内酯化反应中观测到的区域选择性，与已建立的不对称亲电氟化方案所得到的结果互为补充。