1: 43.9 percent / pyridine-borane complex / ethanol; H2O / 3 h / Ambient temperature 2: 55 percent / methyllithium, tert-butyllithium, water / diethyl ether; hexane; pentane / 48 h / Ambient temperature View Scheme

Multi-step reaction with 2 steps 1: 43.9 percent / pyridine-borane complex / ethanol; H2O / 3 h / Ambient temperature2: 11.5 percent / methyllithium, tert-butyllithium, water / diethyl ether; hexane; pentane / 48 h / Ambient temperature