Abstract A series of isomeric methoxy-2-alkynes were hydroborated to determine the effect of the methoxy group on the direction of the hydroboration. The effect of the methoxy group is to direct the boron atom to the side of the triple bond nearest to it. The magnitude of the directive effect increases as the methoxy group approaches the site of unsaturation. However, steric interactions become significant when the substituent is adjacent to the ...
