5755-78-2Relevant academic research and scientific papers
Base-Mediated Radical Borylation of Alkyl Sulfones
Huang, Mingming,Hu, Jiefeng,Krummenacher, Ivo,Friedrich, Alexandra,Braunschweig, Holger,Westcott, Stephen A.,Radius, Udo,Marder, Todd B.
supporting information, (2021/12/02)
A practical and direct method was developed for the production of versatile alkyl boronate esters via transition metal-free borylation of primary and secondary alkyl sulfones. The key to the success of the strategy is the use of bis(neopentyl glycolato) diboron (B2neop2), with a stoichiometric amount of base as a promoter. The practicality and industrial potential of this protocol are highlighted by its wide functional group tolerance, the late-stage modification of complex compounds, no need for further transesterification, and operational simplicity. Radical clock, radical trap experiments, and EPR studies were conducted which show that the borylation process involves radical intermediates.
Quaternary Ammonium Trifluoromethoxide Salts as Stable Sources of Nucleophilic OCF3
Britton, Robert,Friesen, Chadron M.,Jelier, Benson J.,Martin, Rainer E.,Meanwell, Michael,Newton, Josiah J.
supporting information, p. 1785 - 1790 (2020/03/24)
The reaction of nucleophilic tertiary amines with trifluoromethyl and pentafluoroethyl methyl ethers provides quaternary ammonium trifluoromethoxide (NR4OCF3) and pentafluoroethoxide (NR4OCF2CF3) salts, respectively, in good yields. The new trifluoromethoxide salts disclosed herein are uniquely stable for extended periods of time in both the solid state and in solution, which complements contemporary reagents. Here we describe the preparation of a range of NR4OCF3 salts, their long-term stability, and utility in substitution reactions.
Development of an enantioselective route toward the lycopodium alkaloids: Total synthesis of lycopodine
Yang, Hua,Carter, Rich G.
supporting information; experimental part, p. 4929 - 4938 (2010/10/21)
(Figure presented) Synthesis of a C15-desmethyl tricycle core of lycopodine has been accomplished. Key steps in the synthetic sequence include organocatalytic, intramolecular Michael addition of a keto sulfone and a tandem 1,3-sulfonyl shift/Mannich cyclization to construct the tricyclic core ring system. Synthetic work toward this natural product family led to the development of N-(p-dodecylphenylsulfonyl)-2-pyrrolidinecarboxamide, an organocatalyst which facilitiates enantioselective, intramolecular Michael additions. A detailed mechanistic discussion is provided for both the intramolecular Michael addition and the sulfone rearrangement. Finally, the application of these discoveries to the enantioselective total synthesis of alkaloid lycopodine is described.
Enantioselective total synthesis of lycopodine
Yang, Hua,Carter, Rich G.,Zakharov, Lev N.
supporting information; experimental part, p. 9238 - 9239 (2009/02/03)
The first enantioselective total synthesis of lycopodine has been completed. Key steps include a highly diastereoselective organocatalyzed cyclization of a keto sulfone to establish the key C7 and C8 stereocenters and a tandem 1,3-su
Synthesis of substituted tetrahydropyrans via intermolecular reactions of δ-halocarbanions with aldehydes
Barbasiewicz, Michal,Brud, Aneta,Majcosza, Mieczyslaw
, p. 1209 - 1213 (2008/02/02)
Intramolecular substitution in δ-halocarbanions leading to cyclobutanes is a relatively slow process, thus they readily add to carbonyl groups; the thus-produced anionic adducts cyclize to tetrahydropyran derivatives. A simple mechanistic discussion, opti
Sulfone derivatives as 5-HT7 receptor ligands
-
Page/Page column 7, (2010/02/09)
The present invention relates to sulfone derivatives of formula (I): Ar—SO2—CR2R3-L-N(R1)2??I wherein Ar, L, R1, R2 and R3 are as defined herein, and pharmaceutically
A new stereoselective synthesis of (±)-grandisol based on the remote alkylation protocol
Monteiro, Hugo J.,Stefani, Helio A.
, p. 2659 - 2663 (2007/10/03)
A new stereoselective synthesis of (±)-grandisol (1a) has been developed. The synthesis starts with a simple cyclobutyl derivative to which the methyl group and the 1,2-cis disposed side chains were appended through a remote alkylation protocol.
γ- and δ-epoxy sulfones. Formation of different ring-sized products upon reaction with CH3MgI or LiN2
Decesare, John M.,Corbel, Bernard,Durst, Tony,Blount, John F.
, p. 1415 - 1424 (2007/10/02)
γ-Epoxy sulfones in which the epoxide function is terminal yield cyclopropylmethanol derivatives on reaction with methylithium or lithium diisopropylamide.In contrast, treatment of these epoxides with two equivalents of CH3MgI gives only cis-3-phenylsulfonylcyclobutanols.The cis-relationship between the OH and sulfonyl groups was proven in one instance by an X-ray stucture determination.Inernal γ-epoxy sulfones yield cyclopropylmethanols with all bases studied.All δ-epoxy sulfones studied furnished cis-3-phenylsulfonylcyclopentanols upon reaction with the Grignard reagent.These same epoxides gave either cyclopentanols or noncyclic products upon reaction with LDA; no cyclobutane ring containing products were obtained contrary to the expectations based on Stork's results with the corresponding epoxy nitriles (ref. 2).The mechanism of the Grignard-mediated reaction involves epoxide opening by iodide ion, α-sulfonyl Grignard formation, and, finally, cyclization.When LDA or CH3Li is used the products are formed by an intramolecular SN2 opening of the epoxide by an α-lithio sulfone.
