41780-84-1Relevant academic research and scientific papers
Umpolung Difunctionalization of Carbonyls via Visible-Light Photoredox Catalytic Radical-Carbanion Relay
Wang, Shun,Cheng, Bei-Yi,Sr?en, Matea,K?nig, Burkhard
supporting information, p. 7524 - 7531 (2020/08/05)
The combination of photoredox catalysis with the Wolff-Kishner (WK) reaction allows the difunctionalization of carbonyl groups by a radical-carbanion relay sequence (photo-Wolff-Kishner reaction). Photoredox initiated radical addition to N-sulfonylhydrazones yields α-functionalized carbanions following the WK-type mechanism. With sulfur-centered radicals, the carbanions are further functionalized by reaction with electrophiles including CO2 and aldehydes, whereas CF3 radical addition furnishes a wide range of gem-difluoroalkenes through β-fluoride elimination of the generated α-CF3 carbanions. More than 80 substrate examples demonstrate the broad applicability of this reaction sequence. A series of investigations including radical inhibition, deuterium labeling, fluorescence quenching, cyclic voltammetry, and control experiments support the proposed radical-carbanion relay mechanism.
Lewis Acid Catalyzed [4 + 2] Cycloaddition of N-Tosylhydrazones with ortho-Quinone Methides
Wang, Chun-Ying,Han, Jia-Bin,Wang, Long,Tang, Xiang-Ying
, p. 14258 - 14269 (2019/11/11)
A formal [4 + 2] cycloaddition of N-tosylhydrazones with ortho-quinone methides was developed, affording the facile synthesis of diverse 1,3-oxazine derivatives under mild conditions. In this transformation, N-tosylhydrazones are used as a 1,2-dipole synt
N-Tosylhydrazone directed annulation via C-H/N-N bond activation in Ru(ii)/PEG-400 as homogeneous recyclable catalytic system: a green synthesis of isoquinolines
Deshmukh, Dewal S.,Bhanage, Bhalchandra M.
supporting information, p. 4864 - 4873 (2018/07/15)
A green and sustainable methodology for the synthesis of isoquinolines using Ru(ii)/PEG-400 as a homogeneous recyclable catalytic system has been demonstrated. N-Tosylhydrazone, a rarely explored directing group, has been successfully employed for an annu
Rhodium-Catalyzed B-H Bond Insertion Reactions of Unstabilized Diazo Compounds Generated in Situ from Tosylhydrazones
Pang, Yue,He, Qiao,Li, Zi-Qi,Yang, Ji-Min,Yu, Jin-Han,Zhu, Shou-Fei,Zhou, Qi-Lin
supporting information, p. 10663 - 10668 (2018/09/06)
Although transition-metal-catalyzed B-H bond insertion of carbenes into stable borane adducts has emerged as a promising method for organoborane synthesis, all the diazo compounds used to date as carbene precursors have had an electron-withdrawing group to stabilize them. Herein, we report a protocol for rhodium-catalyzed B-H bond insertion reactions of unstabilized diazo compounds generated in situ from tosylhydrazones. In addition, by using chiral dirhodium catalysts, we also achieved an asymmetric version of the reaction with good to excellent enantioselectivities (up to 98:2 e.r.). This is the first enantioselective heteroatom-hydrogen bond insertion reaction to use unstabilized diazo compounds as carbene precursors. The protocol exhibited good functional group tolerance and could be carried out on a gram scale. It also enabled one-pot transformation of a carbonyl group to a boryl group enantioselectively. The B-H bond insertion products could be easily transformed into chiral alcohols and other widely used organoboron reagents with enantiomeric fidelity.
Copper-Catalyzed Cyanation of N-Tosylhydrazones with Thiocyanate Salt as the "cN" Source
Huang, Yubing,Yu, Yue,Zhu, Zhongzhi,Zhu, Chuanle,Cen, Jinghe,Li, Xianwei,Wu, Wanqing,Jiang, Huanfeng
, p. 7621 - 7627 (2017/07/26)
A novel protocol for the synthesis of α-aryl nitriles has been successfully achieved via a copper-catalyzed cyanation of N-tosylhydrazones employing thiocyanate as the source of cyanide. The features of this method include a convenient operation, readily available substrates, low-toxicity thiocyanate salts, and a broad substrate scope.
One-step synthesis of sulfonamides from N-tosylhydrazones
Tsai, Andy S.,Curto, John M.,Rocke, Benjamin N.,Dechert-Schmitt, Anne-Marie R.,Ingle, Gajendrasingh K.,Mascitti, Vincent
supporting information, p. 508 - 511 (2016/02/18)
The first described reaction between N-tosylhydrazone and SO2 is reported to provide alkyl sulfonamides in the presence of various amines. In this procedurally simple method, hydrazones of both unsaturated aldehydes and ketones proceed in moder
Reductive coupling reactions: A new strategy for C(sp3)-P bond formation
Chen, Zi-Sheng,Zhou, Zhao-Zhao,Hua, Hui-Liang,Duan, Xin-Hua,Luo, Jian-Yi,Wang, Jia,Zhou, Ping-Xin,Liang, Yong-Min
supporting information, p. 1065 - 1068 (2013/02/25)
The C(sp3)-P bond forming reaction utilizing N-tosylhydrazones as readily available alkylating reagents was developed, which provides a new opportunity for preparing phosphine oxide derivatives with moderate to good yields. This reductive coupling reaction is proposed to proceed through an insertion of copper carbene into P-H bond of H-phosphorus oxides. The salient features of the reaction are operational simplicity and functional-group tolerance.
Copper-catalyzed direct ortho-alkylation of N-iminopyridinium ylides with N-tosylhydrazones
Xiao, Qing,Ling, Lin,Ye, Fei,Tan, Renchang,Tian, Leiming,Zhang, Yan,Li, Yuxue,Wang, Jianbo
supporting information, p. 3879 - 3885 (2013/05/22)
Copper-catalyzed cross-coupling of N-tosylhydrazones with N-iminopyridinium ylides leads to the direct C-H alkylation. This direct C-H bond alkylation transformation uses inexpensive CuI as the catalyst without any ligand. The reaction is operationally simple and conducted under mild conditions, giving the corresponding alkylated pyridines in moderate to good yields. DFT calculation provides insights into the reaction mechanism, suggesting that the reaction proceeds through the Cu carbene migratory insertion process.
Palladium-catalyzed cross-coupling of cyclopropylmethyl N-tosylhydrazones with aromatic bromides: An easy access to multisubstituted 1,3-butadienes
Yang, Qin,Chai, Huining,Liu, Tingting,Yu, Zhengkun
supporting information, p. 6485 - 6489 (2013/11/19)
Direct synthesis of 1,1-disubstitued 1,3-butadienes has been efficiently realized from the cross-coupling of cyclopropylmethyl N-tosylhydrazones with aromatic bromides by means of PdCl2(MeCN)2 as catalyst. 1,1,4-Trisubstitued 1,3-but
C(sp)-C(sp3) bond formation through cu-catalyzed cross-coupling of N -tosylhydrazones and trialkylsilylethynes
Ye, Fei,Ma, Xiaoshen,Xiao, Qing,Li, Huan,Zhang, Yan,Wang, Jianbo
supporting information; experimental part, p. 5742 - 5745 (2012/05/07)
Copper-catalyzed cross-coupling of N-tosylhydrazones with trialkylsilylethynes leads to the formation of C(sp)-C(sp3) bonds. Cu carbene migratory insertion is proposed to play the key role in this transformation.
