69957-36-4Relevant academic research and scientific papers
A Titanium-Catalyzed Reductive α-Desulfonylation
Kern, Christoph,Selau, Jan,Streuff, Jan
supporting information, p. 6178 - 6182 (2021/03/16)
A titanium(III)-catalyzed desulfonylation gives access to functionalized alkyl nitrile building blocks from α-sulfonyl nitriles, circumventing traditional base-mediated α-alkylation conditions and strong single electron donors. The reaction tolerates numerous functional groups including free alcohols, esters, amides, and it can be applied also to the α-desulfonylation of ketones. In addition, a one-pot desulfonylative alkylation is demonstrated. Preliminary mechanistic studies indicate a catalyst-dependent mechanism involving a homolytic C?S cleavage.
Efficient Diastereoselective Syntheses of erythro- Or threo-a-Alkyl-β-hydroxy Sulfones by Reductions of α-Alkyl-β-keto Sulfones with TiCI4/BHg or LiEtsBH/CeCl3, Respectively
Marcantoni, Enrico,Cingolani, Simone,Bartoli, Giuseppe,Bosco, Marcella,Sambri, Letizia
, p. 3624 - 3630 (2007/10/03)
A stereoselective synthesis of erythro- and threo-α-alkyl-β-hydroxy sulfones by reduction of the corresponding α-alkyl-β-keto sulfones has been developed. The pivotal role in this methodology is played by the chelating or nonchelating properties of the Lewis acid employed. The strong chelating TiCl4 led to the erythro isomer in high diastereomeric excess in noncoordinating solvents (CH2Cl2) at -78 °C using BH3/py as reducing agent, while the nonchelating CeCl3 gave a high excess of the threo isomer in coordinating solvents (THF) at the same temperature using lithium triethylborohydride (LiEt3BH) as reducing agent. Moreover, this methodology has been successfully utilized for the synthesis of α-allyl-β-hydroxy sulfones, which are useful synthetic intermediates to obtain 2,5-disubstituted tetrahydrofurans by electrophilic cyclization.
NAD(P)+-NAD(P)H Models. 65. Photochemical Reductive Desulfonylation of β-Keto Sulfones with Hantzsch Ester
Fujii, Masayuki,Nakamura, Kaoru,Mekata, Hidevuki,Oka, Shinzaburo,Ohno, Atsuyoshi
, p. 495 - 500 (2007/10/02)
A new procedure for the reductive desulfonylation of β-keto sulfones is described.The reaction proceeds under a photochemical conditions with the Hantzsch ester in pyridine in the presence of ruthenium(II).Various functional groups are unaffected under the reaction conditions.Application of the procedure to the syntheses of certain natural products is also described.
