2-(R)-(3-(R)-(Hydroxymethyl)-4-(S)-(3-fluorophenyl) pyrrolidin-1-yl)-2-(R),3-dimethylbutanoic acid 、 2-(R)-(3-(R)-(hydroxymethyl)-4-(S)-(3-fluorophenyl)pyrrolidin-1-yl)-2-(R),3-dimethylbutanoic acid, p-methoxybenzyl ester 以88%的产率得到2-(R)-(3-(R)-(Formyl)-4-(S)-(3-fluorophenyl)pyrrolidin-1-yl)-2-(R),3-dimethylbutanoic Acid