1: 1.) LDA / 1.) THF, -40 deg C, 10 min 2.) 1h, RT, 2: trimethylphosphite / tetrahydrofuran / 1 h / Ambient temperature View Scheme

(i) LDA, THF, (ii) /BRN= 969135/, (iii) P(OMe)3, MeOH; Multistep reaction;