One and Two-Carbon Homologation of Primary and Secondary Alcohols to Corresponding Carboxylic Esters Using β-Carbonyl BT Sulfones as a Common Intermediate

0489842 - ÚEB 2019 RIV US eng J - Článek v odborném periodiku
Bon, D.J.Y.D. - Kováč, O. - Ferugová, V. - Zálešák, F. - Pospíšil, Jiří
One and Two-Carbon Homologation of Primary and Secondary Alcohols to Corresponding Carboxylic Esters Using β-Carbonyl BT Sulfones as a Common Intermediate.
Journal of Organic Chemistry. Roč. 83, č. 9 (2018), s. 4990-5001. ISSN 0022-3263. E-ISSN 1520-6904
Grant CEP: GA MŠMT(CZ) LO1304; GA MŠMT(CZ) LO1204
Institucionální podpora: RVO:61389030
Klíčová slova: ALPHA-DIAZOCARBONYL COMPOUNDS * RADICAL-MEDIATED CLEAVAGE * STEREOSELECTIVE ALKYLATION
Obor OECD: Organic chemistry
Impakt faktor: 4.745, rok: 2018

Herein we report the efficient one- and two-carbon homologation of 1° and 2° alcohols to their corresponding homologated esters via the Mitsunobu reaction using β-carbonyl benzothiazole (BT) sulfone intermediates. The one-carbon homologation approach uses standard Mitsunobu C-S bond formation, oxidation and subsequent alkylation, while the two-carbon homologation uses a less common C-C bond forming Mitsunobu reaction. In this latter case, the use of β-BT sulfone bearing esters lowers the pK a sufficiently enough for the substrate to be used as a carbon-based nucleophile and deliver the homologated β-BT sulfone ester, and this superfluous sulfone group can then be cleaved. In this paper we describe several methods for the effective desulfonylation of BT sulfones and have developed methodology for one-pot alkylation-desulfonylation sequences. As such, overall, a one-carbon homologation sequence can be achieved in a two-pot (four step) procedure and the two-carbon homologation in a two-pot (three step) procedure (three-pot, four step when C-acid synthesis is included). This methodology has been applied to a wide variety of functionality (esters, silyl ethers, benzyls, heteroaryls, ketones, olefins and alkynes) and are all tolerated well providing good to very good overall yields. The power of our method was demonstrated in site-selective ingenol C20 allylic alcohol two-carbon homologation.
Trvalý link: http://hdl.handle.net/11104/0284175