- Copper-Catalyzed Enantioselective Construction of Tertiary Propargylic Sulfones
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Tertiary propargylic sulfones are of significant importance in organic synthesis and medicinal chemistry, but to date no general asymmetric synthesis approach has been developed. We disclose a versatile copper-catalyzed sulfonylation of propargylic cyclic carbonates using sodium sulfinates that allows the construction of propargylic sulfones featuring elusive quaternary stereocenters. This method provides the first successful example of such an enantioselective propargylic sulfonylation, features high asymmetric induction, wide functional group tolerance, and scalability, and enables attractive product diversification.
- Gómez, José Enrique,Cristòfol, àlex,Kleij, Arjan W.
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supporting information
p. 3903 - 3907
(2019/02/24)
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- Diastereoselective Monofluorocyclopropanation Using Fluoromethylsulfonium Salts
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Diarylfluoromethylsulfonium salts, alternatives to freons or advanced fluorinated building blocks, are bench stable and easy-to-use sources of direct fluoromethylene (:CHF) transfer to alkenes. These salts enabled development of a trans-selective monofluorinated Johnson-Corey-Chaykovsky reaction with vinyl sulfones or vinyl sulfonamides to access synthetically challenging monofluorocyclopropane scaffolds. The described method offers rapid access to monofluorinated cyclopropane building blocks with further functionalization opportunities to deliver more complex synthetic targets diastereoselectively.
- Melngaile, Renate,Sperga, Arturs,Baldridge, Kim K.,Veliks, Janis
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supporting information
p. 7174 - 7178
(2019/09/12)
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- Regio- and Enantioselective Preparation of Chiral Allylic Sulfones Featuring Elusive Quaternary Stereocenters
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We describe here the first general asymmetric synthesis of sterically encumbered α,α-disubstituted allylic sulfones via Pd-catalyzed allylic substitution. The design and application of a new and highly efficient phosphoramidite ligand (L10) proved to be crucial, and a wide variety of challenging allylic sulfones featuring quaternary stereocenters could be obtained in good yields and with good to excellent levels of regio- and enantioselectivities under attractive process conditions. The developed methodology employs easily accessible chemical feedstock including racemic allylic precursors and sodium sulfinates. The utility of the method is further demonstrated by the synthesis of the sesquiterpene (?)-Agelasidine A.
- Cai, Aijie,Kleij, Arjan W.
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supporting information
p. 14944 - 14949
(2019/11/05)
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- Direct Substitution of Secondary and Tertiary Alcohols to Generate Sulfones under Catalyst- and Additive-Free Conditions
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An environmentally benign protocol that affords propargylic sulfones containing highly congested carbon centers from easily accessible alcohols and sulfinic acids with water as the only byproduct is reported. The reaction proceeded via an in situ dehydrative cross-coupling process by taking advantage of the synergetic actions of multiple hydrogen bonds rather than relying on an external catalyst and/or additives to achieve high product distribution.
- Liu, Yanan,Xie, Peizhong,Sun, Zuolian,Wo, Xiangyang,Gao, Cuiqing,Fu, Weishan,Loh, Teck-Peng
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supporting information
p. 5353 - 5356
(2018/09/13)
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- Eosin Y (EY) Photoredox-Catalyzed Sulfonylation of Alkenes: Scope and Mechanism
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Alkyl- and aryl vinyl sulfones were obtained by eosin Y (EY)-mediated visible-light photooxidation of sulfinate salts and the reaction of the resulting S-centered radicals with alkenes. Optimized reaction conditions, the sulfinate and alkene scope, and X-ray structural analyses of several reaction products are provided. A detailed spectroscopic study explains the reaction mechanism, which proceeds through the EY radical cation as key intermediate oxidizing the sulfinate salts.
- Meyer, Andreas Uwe,Straková, Karolína,Slanina, Tomá?,K?nig, Burkhard
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supporting information
p. 8694 - 8699
(2016/07/07)
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- CRTH2 MODULATORS
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Modulators of CRTH2, particularly antagonists of CRTH2, that are useful for treating various disorders, including asthma and respiratory disorders are disclosed. The compounds fall within a genus described by formula I
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Page/Page column 204
(2010/04/27)
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- Silver sulfinate physical developer for heat-developable photographic films
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Improved heat developable silver films are produced upon coating and drying a binder composition containing (a) a substantially light-insensitive silver sulfinate, (b) a silver halide photocatalyst, and (c) a developer. A preferred film contains (a) silve
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- A CONVENIENT AND GENERAL SYNTHESIS OF ALKANE SULFINIC ACIDS
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2-(Alkylsulfonyl)benzothiazoles are reduced with sodium tetrahydroborate to give alkane sulfinic acids in good yield.
- Ueno, Yoshio,Kojima, Akihiko,Okawara, Makoto
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p. 2125 - 2128
(2007/10/02)
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- INVESTIGATION IN THE REGION OF THIOSULFONIC ACIDS. XXXII. REACTION OF ARYL ESTERS OF THIOSULFONIC ACIDS WITH SUBSTANCES CONTAINING AN ACTIVE METHYLENE GROUP
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The reactions of the aryl esters of thisulfonic acids with diethyl malonate, ethyl acetoacetate, ethyl cyanoacetate, and acetylacetone in the presence of sodium alcoholates were investigated at various temperatures.Without heat the reaction takes place with the formation of sulfinates and arenesufenic esters, which form their thio derivatives when heated with substances containing an active methylene group in the presence of sodium alcoholates.It was thus demonstrated that under the investigated conditions thioarylating characteristics are exhibited not by the aryl esters of the thiosulfonic acids but by the esters of arenesufenic acids formed as the initial products of these reactions.
- Boldyrev, B. G.,Aristarkhova, L. N.,Stoyanovskaya, Ya. I.,Bilozor, T. K.
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p. 1160 - 1167
(2007/10/02)
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