Synthesis of N,N-Diethylbenzamides via a Non-Classical Mitsunobu Reaction.

The use of the Mitsunobu reaction for the synthesis of N,N-diethylbenzamides affords ortho-, meta-, and para-substituted benzamides, containing both electron-donating and electron-withdrawing groups. While the preparation of numerous functional groups has been efficiently demonstrated employing the Mitsunobu reaction, our methodology represents the first application of the Mitsunobu reaction for the construction of benzamides using benzoic acid and amine starting materials. Moreover, this synthetic transformation is believed to proceed via a non-classical mechanism involving the existence of an acyloxyphosphonium ion.

Preparation of C-arylglycals via Suzuki-Miyaura cross-coupling of dihydropyranylphosphates.

The preparation of C-arylglycals has been accomplished employing the Suzuki-Miyaura cross-coupling reaction of dihydropyranylphosphates with arylboronate esters. The reaction is tolerant of both electron-donating (EDG) and electron-withdrawing (EWG) groups on the aromatic ring and affords the corresponding C-arylglycals in good to excellent yields (68-97%). Additionally, the ketene acetal phosphate derived from 6-deoxy-3,4-di-O-benzyl-L-rhamnal also couples efficiently to yield C-arylglycals in excellent yields.