135579-85-0Relevant articles and documents
Enantioconvergent and Regioselective Synthesis of Allenylsilanes by Nickel-Catalyzed C(sp2)-C(sp3) Cross-Coupling Starting from Racemic α-Silylated Propargylic Bromides
Xu, Yan,Yi, Hong,Oestreich, Martin
supporting information, p. 2194 - 2197 (2021/05/07)
A direct synthesis of enantioenriched allenylsilanes from racemic α-silylated propargylic bromides by an enantioconvergent nickel-catalyzed cross-coupling is reported. The high regioselectivity is governed by the bulky silyl group, and the C(sp2)-C(sp3) bond formation occurs exclusively at the γ-position of the propargyl electrophile. The level of enantioselection induced by a chiral Pybox ligand is moderate.
Enantio- and Regioconvergent Nickel-Catalyzed C(sp3)?C(sp3) Cross-Coupling of Allylic Electrophiles Steered by a Silyl Group
Kranidiotis-Hisatomi, Nektarios,Oestreich, Martin,Yi, Hong
supporting information, p. 13652 - 13655 (2021/05/10)
A two-step sequence for the enantio- and diastereoselective synthesis of exclusively alkyl-substituted acyclic allylic systems with a stereocenter in the allylic position is reported. The asymmetric induction and the site selectivity are controlled in an
Selective synthesis of enol ethers: Via nickel-catalyzed cross coupling of α-oxy-vinylsulfones with alkylzinc reagents
Gong, Liang,Zhang, Qian,Xie, Demeng,Zhang, Wei,Xu, Shi-Yang,Zhang, Xia,Niu, Dawen
supporting information, p. 12273 - 12276 (2021/11/30)
We describe here a Ni-catalyzed Negishi coupling reaction to prepare 1,2-dialkyl enol ethers in a stereoconvergent fashion. This method employs readily available and bench-stable α-oxy-vinylsulfones as electrophiles. The C-sulfone bond in the α-oxy-vinylsulfone motif is cleaved chemoselectively in these reactions. The mild conditions are tolerant of a variety of functional groups on both partners, thus representing a general strategy for enol ether synthesis. This unique reactivity of α-oxy-vinylsulfones indicates their further application as electrophilic partners in cross-coupling reactions.
Cobalt-Catalyzed Cross-Coupling of Functionalized Alkylzinc Reagents with (Hetero)Aryl Halides
Grokenberger, Lucie,Hammann, Jeffrey M.,Karaghiosoff, Konstantin,Knochel, Paul,Lutter, Ferdinand H.,Spie?, Philipp
supporting information, p. 5546 - 5550 (2020/02/26)
A combination of 10 % CoCl2 and 20 % 2,2′-bipyridine ligands enables cross-coupling of functionalized primary and secondary alkylzinc reagents with various (hetero)aryl halides. Couplings with 1,3- and 1,4-substituted cycloalkylzinc reagents proceeded diastereoselectively leading to functionalized heterocycles with high diastereoselectivities of up to 98:2. Furthermore, alkynyl bromides react with primary and secondary alkylzinc reagents providing the alkylated alkynes.
Enantioselective Construction of α-Chiral Silanes by Nickel-Catalyzed C(sp3)?C(sp3) Cross-Coupling
Yi, Hong,Mao, Wenbin,Oestreich, Martin
supporting information, p. 3575 - 3578 (2019/02/16)
An enantioselective C(sp3)?C(sp3) cross-coupling of racemic α-silylated alkyl iodides and alkylzinc reagents is reported. The reaction is catalyzed by NiCl2/(S,S)-Bn-Pybox and yields α-chiral silanes with high enantiocontr
Enantioconvergent Cross-Couplings of Alkyl Electrophiles: The Catalytic Asymmetric Synthesis of Organosilanes
Schwarzwalder, Gregg M.,Matier, Carson D.,Fu, Gregory C.
supporting information, p. 3571 - 3574 (2019/02/13)
Metal-catalyzed enantioconvergent cross-coupling reactions of alkyl electrophiles are emerging as a powerful tool in asymmetric synthesis. To date, high enantioselectivity has been limited to couplings of electrophiles that bear a directing group or a pro
Csp3-Csp3 Bond-Forming Reductive Elimination from Well-Defined Copper(III) Complexes
Paeth, Matthew,Tyndall, Sam B.,Chen, Liang-Yu,Hong, Jia-Cheng,Carson, William P.,Liu, Xingwu,Sun, Xiaodong,Liu, Jinjia,Yang, Kundi,Hale, Elizabeth M.,Tierney, David L.,Liu, Bin,Cao, Zhi,Cheng, Mu-Jeng,Goddard, William A.,Liu, Wei
supporting information, p. 3153 - 3159 (2019/03/06)
Carbon-carbon bond-forming reductive elimination from elusive organocopper(III) complexes has been considered the key step in many copper-catalyzed and organocuprate reactions. However, organocopper(III) complexes with well-defined structures that can undergo reductive elimination are extremely rare, especially for the formation of Csp3-Csp3 bonds. We report herein a general method for the synthesis of a series of [alkyl-CuIII-(CF3)3]- complexes, the structures of which have been unequivocally characterized by NMR spectroscopy, mass spectrometry, and X-ray crystal diffraction. At elevated temperature, these complexes undergo reductive elimination following first-order kinetics, forming alkyl-CF3 products with good yields (up to 91%). Both kinetic studies and DFT calculations indicate that the reductive elimination to form Csp3-CF3 bonds proceeds through a concerted transition state, with a ΔH? = 20 kcal/mol barrier.
Access to Functionalized Quaternary Stereocenters via the Copper-Catalyzed Conjugate Addition of Monoorganozinc Bromide Reagents Enabled by N, N-Dimethylacetamide
Fulton, Tyler J.,Alley, Phebe L.,Rensch, Heather R.,Ackerman, Adriana M.,Berlin, Cameron B.,Krout, Michael R.
, p. 14723 - 14732 (2018/11/23)
Monoorganozinc reagents, readily obtained from alkyl bromides, display excellent reactivity with β,β-disubstituted enones and TMSCl in the presence of Cu(I) and Cu(II) salts to synthesize a variety of cyclic functionalized β-quaternary ketones in 38-99% yields and 9:1-20:1 diastereoselectivities. The conjugate addition features a pronounced improvement in DMA using monoorganozinc bromide reagents. A simple one-pot protocol that harnesses in situ generated monoorganozinc reagents delivers comparable product yields.
Nickel-Catalyzed Alkyl-Alkyl Cross-Couplings of Fluorinated Secondary Electrophiles: A General Approach to the Synthesis of Compounds having a Perfluoroalkyl Substituent
Liang, Yufan,Fu, Gregory C.
supporting information, p. 9047 - 9051 (2015/08/03)
Fluorinated organic molecules are of interest in fields ranging from medicinal chemistry to polymer science. Described herein is a mild, convenient, and versatile method for the synthesis of compounds bearing a perfluoroalkyl group attached to a tertiary carbon atom by using an alkyl-alkyl cross-coupling. A nickel catalyst derived from NiCl2 glyme and a pybox ligand achieves the coupling of a wide range of fluorinated alkyl halides with alkylzinc reagents at room temperature. A broad array of functional groups is compatible with the reaction conditions, and highly selective couplings can be achieved on the basis of differing levels of fluorination. A mechanistic investigation has established that the presence of 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) inhibits cross-coupling under these conditions and that a TEMPO-electrophile adduct can be isolated.
A general strategy for the synthesis of enantiomerically pure azetidines and aziridines through nickel-catalyzed cross-coupling
Jensen, Kim L.,Nielsen, Dennis U.,Jamison, Timothy F.
supporting information, p. 7379 - 7383 (2015/05/13)
Abstract In this communication, we report a straightforward synthesis of enantiomerically pure 2-alkyl azetidines. The protocol is based on a highly regioselective nickel-catalyzed cross-coupling of aliphatic organozinc reagents with an aziridine that fea
