“…[34][35][36] The copper catalyst system, comprising of copper-bis(oxazoline) ligand-NaBARF, has been demonstrated by the Maguire group to effect C-H insertion reactions with very high levels of enantiocontrol across a diverse range of α-diazocarbonyl substrates leading to tetrahydrothiopyrans-S,S-dioxides, sulfolanes, cyclopentanones, β-and γlactams (Scheme 2, A). [34][35][36][37][38][39][40] Of particular interest to this study were the reactions conducted in our team by Flynn 34 and later expanded upon by Shiely 36 concerning the copper-bis(oxazoline) catalysed asymmetric transformations of α-diazo-β-keto sulfones to tetrahydrothiopyrans-S,S-dioxides (up to 98% ee, Scheme 2, A).…”