Novel synthesis of chiral terminal allenes via palladium(0)-catalyzed reduction of mesylates of 2-bromoalk-2-en-1-ols bearing a protected amino group, using diethylzinc

A novel palladium(0)-catalyzed synthetic route to a series of chiral terminal allenes bearing an N-protected amino alkyl group has been developed. The palladium(0)-catalyzed reaction of mesylates of 2-bromoalk-2-en-1-ols bearing an amino functionality, with diethylzinc affords the corresponding terminal allenes in good yields. Both (E)- and (Z)-bromomesylates can equally be used for the present reaction, yielding the desired allenes in comparable yields.