4,4-dimethyl-A-homo-5-cholesten-3-one                                                                                                                                                              在
                                                                                                                                                                                 phenyltrimethylammonium tribromide                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
乙二醇二甲醚                                                                                  为溶剂,
                                                                                                                                                    反应 5.0h,
                                                                                                                以433 mg的产率得到(1R,3aS,3bS,10aR,10bS,12aR)-9-Bromo-1-((R)-1,5-dimethyl-hexyl)-7,7,10a,12a-tetramethyl-2,3,3a,3b,4,6,7,9,10,10a,10b,11,12,12a-tetradecahydro-1H-cyclohepta[a]cyclopenta[f]naphthalen-8-one