3,4-syn-3-<(tert-butyldimethylsilyl)oxy>-5-<(trimethylsilyl)oxy>-2,4-dimethyl-5-heptene   、                                                                                      
(2S,3R)-3-(tert-Butyl-dimethyl-silanyloxy)-2,4-dimethyl-pentanal                                                                                                                                                              在
                                                                                                                                                                                 
三氟化硼乙醚                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
二氯甲烷                                                                                  为溶剂,
                                                                                                                                                                                        以74%的产率得到(3R,4S,6S,7R,8R,9R)-3,9-Bis-(tert-butyl-dimethyl-silanyloxy)-7-hydroxy-2,4,6,8,10-pentamethyl-undecan-5-one