Fig. 3: Optimization of the asymmetric addition to [1.1.1]propellane.
From: Direct catalytic asymmetric synthesis of α-chiral bicyclo[1.1.1]pentanes
a Optimization of reaction conditions. Entries 2-10 were conducted using an 18 W blue LED lamp at 10 °C. All yields are isolated yields. aDME:Et2O (1:1, 0.2 M). b A survey of H-atom sources (50 mol% loading) shows HAT catalyst 10 is optimal. c A survey of organocatalysts (25 mol% loading) shows catalyst 9 is optimal. d A survey of photocatalysts shows a range of iridium photocatalysts are effective; see the Supplementary Table 4 for details of reduction potentials. Co-solvents were screened as a 2:1 ratio of co-solvent to Et2O (from the solution of 1), with an overall concentration of 0.2 M. For full details of reaction optimization, see Supplementary Tables 1–7. n.r. no reaction.
