. Give the major organic product of each of the reactions in the boxes below. Show the proper stereochemistry where appropriate. For each reaction that gives a pair of enantiomers, you need only give one for full credit. The answer No Reaction may be a valid answer.

50CCH3CH2OH 1. NaOCH3 2. H3O+ 1. PBr3, pyridine 2. NaCN, acetone, 0C \begin{tabular}{l} NaOCH3 \\ HOCH3 \\ \hline \end{tabular} CH2Cl2PCC 0CDMSDMSN CH3C=C3HHr(CH3)2CuLi