Regioselective, tin-free sulfation of a number of unprotected glycopyranosides derived from L-fucose, L-rhamnose, D-arabinose, D-glucose, D-galactose, and D-trehalose was achieved by using phenylboronic acid for masking the hydroxy groups and a 2,2,2-trichloroethyl-protected sulfurylimidazolium salt as the sulfating reagent. The formation of phenylborate es-

The application of 2,6-bis(trifluoromethyl)phenyl boronic acid ( o-FXylB(OH); o-FXyl = 2,6-(CF)CH) as a recoverable and reusable protective agent for diols is described. The resulting cyclic boronic esters are water- and air-stable and tolerant to various organic transformations. Moreover, they can be deprotected under mild conditions. This methodology was applied to the synthesis of a highly conjugated enetriyne natural product with anti-angiogenic activities.

Total synthesis of seminolipid was accomplished via regioselective protection using 2,6-bis(trifluoromethyl)phenylboronic acid followed by regioselective trichloroethyl-protected sulfation as key steps.

for masking the hydroxy groups and a 2,2,2‐trichloroethyl‐protected sulfurylimidazolium salt as the sulfating reagent