10.1021/acs.orglett.8b00479.s001 Xiaojing Liu Xiaojing Liu Junhao Jia Junhao Jia Yuanliang Jia Yuanliang Jia He Gu He Gu Jingwen Luo Jingwen Luo Xiaochuan Chen Xiaochuan Chen A Flexible and Divergent Strategy to Flavonoids with a Chiral A‑Ring Featuring Intramolecular Michael Addition: Stereoselective Synthesis of (+)-Cryptocaryone, (+)-Cryptogione F, and (+)-Cryptocaryanones A and B, as Well as (+)-Cryptochinones A and C American Chemical Society 2018 cryptogione chiral flavonoids Cryptocaryanone Stereoselective Synthesis boron-mediated aldol condensation Flexible Featuring C -7 oxy Flavonoid cryptocaryone Cryptocaryone Cryptochinone 2- deoxy-d-ribose cyclization strategy cryptocaryanone diketone chiral A-ring Intramolecular approach Chiral cryptochinone yield stereoselective synthesis olefinic bonds stereoselective intramolecular Michael addition Cryptogione Divergent Strategy 2018-03-19 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/A_Flexible_and_Divergent_Strategy_to_Flavonoids_with_a_Chiral_A_Ring_Featuring_Intramolecular_Michael_Addition_Stereoselective_Synthesis_of_-Cryptocaryone_-Cryptogione_F_and_-Cryptocaryanones_A_and_B_as_Well_as_-Cryptochinones_A_and_C/6000185 A flexible strategy has been developed to synthesize divergent flavonoids bearing a chiral A-ring. As two key steps, the coupling via a boron-mediated aldol condensation and the cyclization via a highly stereoselective intramolecular Michael addition of 1,3-diketone proceed under mild conditions; thus, the chiral flavonoids bearing C-7 oxy functional groups or olefinic bonds are both easily accessible. Using this approach, the first synthesis of (+)-cryptogione F, (+)-cryptocaryanone B, and (+)-cryptochinones A and C, as well as stereoselective synthesis of (+)-cryptocaryone and (+)-cryptocaryanone A, were achieved from 2-deoxy-d-ribose in high overall yields.