- One-pot asymmetric synthesis of either diastereomer of tert-butanesulfinyl- protected amines from ketones
-
A one-pot method for the asymmetric synthesis of tert-butanesulfinyl- protected amines is described. Condensation of aryl alkyl and dialkyl ketones with tert-butanesulfinamide followed by in situ reduction with the appropriate reagent provides either dias
- Tanuwidjaja, Jessica,Peltier, Hillary M.,Ellman, Jonathan A.
-
-
Read Online
- Efficient Synthesis of Cyclic Sulfoximines from N-Propargylsulfinamides through Sulfur–Carbon Bond Formation
-
Cyclic sulfoximines were readily synthesized by the cyclization of N-propargylsulfinamides without using expensive and toxic metal catalysts. This cyclization proceeded without loss of optical purity of chiral sulfinamides through the unusual sulfur–carbon bond formation promoted by an inexpensive inorganic base. This stereospecific cyclization offers a general approach to the asymmetric synthesis of chiral cyclic sulfoximines as an emerging heterocycle in medicinal chemistry.
- Aota, Yusuke,Maeda, Yoshiaki,Kano, Taichi,Maruoka, Keiji
-
supporting information
p. 15755 - 15758
(2019/11/16)
-
- Highly efficient asymmetric construction of quaternary carbon-containing homoallylic and homopropargylic amines
-
A highly efficient method for the asymmetric synthesis of chiral quaternary carbon-containing homoallylic and homopropargylic amines under mild conditions was achieved with good yields and high diastereoselectivities.
- Guo, Tao,Song, Ran,Yuan, Bin-Hua,Chen, Xiao-Yang,Sun, Xing-Wen,Lin, Guo-Qiang
-
supporting information
p. 5402 - 5404
(2013/07/28)
-
- Indium-promoted diastereo- and regioselective propargylation of chiral sulfinylimines
-
The reaction of different chiral imines 3 derived from aldehydes or ketones with the silylated propargyl bromide 4b under sonication in the presence of indium metal led mainly or exclusively to the formation of protected homopropargylamines 5 in a diaster
- Garcia-Munoz, M. Jesus,Zacconi, Flavia,Foubelo, Francisco,Yus, Miguel
-
supporting information
p. 1287 - 1295
(2013/04/10)
-
- Cycloaddition of chiral tert -butanesulfinimines with trimethylenemethane
-
The cycloaddition of chiral tert-butanesulfinimines with trimethylenemethane is found to give facile access to methylene-pyrrolidines with good yields and diastereoselectivities. The full scope of the cycloaddition is explored, and a range of transformations of the formed methylenepyrrolidines to give a range of functionalized chiral pyrrolidines is presented.
- Procopiou, George,Lewis, William,Harbottle, Gareth,Stockman, Robert A.
-
supporting information
p. 2030 - 2033
(2013/06/05)
-
- Reversal of diastereofacial selectivity in hydride reductions of N-tert-butanesulfinyl imines
-
A variety of N-tert-butanesulfinyl imines were reduced with NaBH 4 in THF containing 2% water to provide the corresponding secondary sulfinamides in high yield and diastereoselectivity. By using the same sulfinyl imine starting materials and changing the reductant to L-Selectride, the stereoselectivity could be efficiently reversed to afford the opposite product diastereomer in high yield and selectivity.
- Colyer, John T.,Andersen, Neil G.,Tedrow, Jason S.,Soukup, Troy S.,Faul, Margaret M.
-
p. 6859 - 6862
(2007/10/03)
-
- Synthesis of enantiomerically pure N-tert-butanesulfinyl imines (tert- butanesulfinimines) by the direct condensation of tert-butanesulfinamide with aldehydes and ketones
-
Experimental details for the first general methods for the one-step preparation of N-tert-butanesulfinyl imines (tert-butanesulfinimines) (2) from aldehydes and ketones is described. To effect the condensations of tert- butanesulfinamide (1) with aldehydes, the Lewis acidic dehydrating agents MgSO4, CuSO4, or Ti(OEt)4 are employed. Aldehyde condensations mediated by MgSO4 proceed in high yields (84-96%) when an excess of aldehyde is used. In contrast, only a slight excess of aldehyde (1.1 equiv) relative to tert- butanesulfinamide provides sulfinimines in high yields when the more Lewis acidic dehydrating agent CuSO4 is used. The CuSO4-mediated procedure is effective for a wide range of aldehydes, including sterically demanding aldehydes, such as isobutyraldehyde (90%), and electron-rich aldehydes, such as p-anisaldehyde (81%). The still more Lewis acidic Ti(OEt)4 and TI(O-i- Pr)4 also afford N-tert-butanesulfinyl aldimines from especially unreactive aldehydes, such as pivaldehyde (82%). In addition, Ti(OEt)4 is effective for the condensation of 1 with ketones to afford a wide range of N-tert- butanesulfinyl ketimines in good yields (77-91%). For sulfinyl ketimines derived from methyl or n-alkyl phenyl ketones and methyl or n-alkyl isopropyl ketones, only the E isomer is detected by 1H and 13C NMR in CDCl3. For those cases where the difference in steric demand about the imine is very small, such as for 2-hexanone, high E/Z ratios are still observed (5:1).
- Liu,Cogan,Owens,Tang,Ellman
-
p. 1278 - 1284
(2007/10/03)
-
- Catalytic asymmetric oxidation of tert-butyl disulfide. Synthesis of tert-butanesulfinamides, tert-butyl sulfoxides, and tert-butanesulfinimines
-
The first example of the catalytic asymmetric oxidation of tert-butyl disulfide (1) is described. The product, tert-butyl tert-butanethiosulfinate (2) is obtained with 91% enantiomeric excess in yields of ≤92% on scales as large as 1 mol. The application of H2O2 as stoichiometric oxidant in the presence of 0.25 mol% of VO(acac)2 and 0.26 mol% of a chiral Schiff base ligand, 6a, is both convenient and cost-effective. Thiosulfinate ester 2 is chemically and optically stable and serves as an excellent precursor to chiral tert-butanesulfinyl compounds by the stereospecific nucleophilic displacement of tert-butyl thiolate. Addition of LiNH2 in liquid ammonia and THF provides tert-butanesulfinamide (3; 91% yield). A single recrystallization provides enantiomerically pure 3 in 71-75% overall yield from disulfide 1. Enantiomerically pure thiosulfinate ester 2 also reacts readily and stereospecifically with Grignard reagents, organolithiums, lithium amides, and lithium imine salts to provide enantiomerically pure chiral sulfoxides, sulfinamides, and sulfinimines in good yield.
- Cogan, Derek A.,Liu, Guangcheng,Kim, Kyungjin,Backes, Bradley J.,Ellman, Jonathan A.
-
p. 8011 - 8019
(2007/10/03)
-