boron triethoxide; (1R,2R,4aS,7R,8aR,9aS)-2-isopropenyl-1-isopropyl-4,4,7-trimethyldecahydro-9-oxa-3a-azacyclopenta[b]naphthalen-1-ol in toluene T=-35°C; 90.5 h; Inert atmosphere; optical yield given as percent eeenantioselective reaction;

(S)-Ph(OH)CCONHBn in toluene T=0°C; 4 h; Title compound not separated from byproducts;

1: tetrahydrofuran / 1 h / -78 °C / Inert atmosphere 2: boron triethoxide; (1R,2R,4aS,7R,8aR,9aS)-2-isopropenyl-1-isopropyl-4,4,7-trimethyldecahydro-9-oxa-3a-azacyclopenta[b]naphthalen-1-ol / toluene / 90.5 h / -35 °C / Inert atmosphere View Scheme