908093-98-1Relevant articles and documents
REACTIONS OF CHLORINE DIOXIDE IN DICHLOROMETHANE I. FORMATION OF RADICAL CATIONS IN ACID MEDIA
Handoo, Kishan L.,Handoo, S. K.,Gadru, Kanchan,Kaul, Anju
, p. 1765 - 1768 (1985)
Chlorine dioxide oxidises electron rich organic compounds to the corresponding radical cations in dichloromethane/TFA medium.In a different experimental set up using alkaline biphasic solvent system, its utility as hydrogen abstractor has been capitalized in the preparation of diazodiphenyl methane in good yield.
1,1-Hydroboration and a Borane Adduct of Diphenyldiazomethane: A Potential Prelude to FLP-N2 Chemistry
Tang, Connie,Liang, Quiming,Jupp, Andrew R.,Johnstone, Timothy C.,Neu, Rebecca C.,Song, Datong,Grimme, Stefan,Stephan, Douglas W.
, p. 16588 - 16592 (2017)
Diphenyldiazomethane reacts with HB(C6F5)2 and B(C6F5)3, resulting in 1,1-hydroboration and adduct formation, respectively. The hydroboration proceeds via a concerted reaction involving ini
Hydrogen bonding switches the spin state of diphenylcarbene from triplet to singlet
Costa, Paolo,Sander, Wolfram
, p. 5122 - 5125 (2014)
Spin specificity is one of the most important properties of carbenes in their reactions. Alcohols are typically used to probe the reactive spin states of carbenes: O-H insertions are assumed to be characteristic of singlet states, whereas C-H insertions a
All-Carbon Tetrasubstituted Olefins Synthesis from Diazo Compounds and Iodonium Ylides under Blue LED Irradiation
Zhao, Yan-Rui,Li, Lei,Xu, Guo-Yong,Xuan, Jun
supporting information, p. 506 - 511 (2021/12/08)
A route for the construction of all-carbon tetra-substituted olefins through visible-light promoted coupling of diazo compounds with iodonium ylides was developed. A wide range of all-carbon tetra-substituted olefins was obtained in moderate to good yields. The synthetic values of the current method were further approved by the synthesis of natural isolates modified alkenes and the successful transformation of final olefins into important heterocycles. (Figure presented.).
Dehalogenative Cross-Coupling of gem-Difluoroalkenes with Alkyl Halides via a Silyl Radical-Mediated Process
Tian, Hao,Yang, Shaoxiang,Wang, Xiaochen,Xu, Wentao,Liu, Yuxiu,Li, Yongqiang,Wang, Qingmin
supporting information, p. 12772 - 12782 (2021/09/13)
Herein, we describe a convenient general protocol for monofluoroalkenylation reactions of alkyl bromides involving cooperative visible-light photoredox catalysis and halogen abstraction. Mechanistic experiments showed that the products were generated by selective cross-coupling of aliphatic radicals with fluoroalkenyl radicals. Silyl radical-mediated halogen abstraction enabled the protocol to be used for the monofluoroalkenylation of a broad range of alkyl and heteroaryl halides. The protocol could be carried out on a gram scale and was applied to cholesterol, indicating its utility for late-stage monofluoroalkenylation reactions.
Copper-Catalyzed Oxidation of Hydrazones to Diazo Compounds Using Oxygen as the Terminal Oxidant
Liu, Wenbin,Twilton, Jack,Wei, Bo,Lee, Maizie,Hopkins, Melissa N.,Bacsa, John,Stahl, Shannon S.,Davies, Huw M. L.
, p. 2676 - 2683 (2021/03/03)
A mild method for accessing diazo compounds via aerobic oxidation of hydrazones is described. This catalytic transformation employs a Cu(OAc)2/pyridine catalyst and molecular oxygen from ambient air as the terminal oxidant, generating water as the sole byproduct and affording the desired diazo compounds within minutes at room temperature. A broad array of electronically diverse aryldiazo esters, ketones, and amides can be accessed. Pyridine dramatically enhances the rate of the reaction by solubilizing the copper catalyst and serving as the Br?nsted base in the turnover-limiting proton-coupled oxidation of hydrazone by copper(II). Insights gained from mechanistic studies led to expansion of the scope of this method to include diaryl hydrazones, delivering diaryl diazomethane derivatives, which cannot be accessed via established diazo transfer methods. The products of this method may be employed in rhodium carbene catalysis without isolation of the diazo intermediate to afford cyclopropane products in good yield with high enantioselectivity.
Photochemical Carbene Transfer Reactions of Aryl/Aryl Diazoalkanes—Experiment and Theory**
Jana, Sripati,Pei, Chao,Empel, Claire,Koenigs, Rene M.
supporting information, p. 13271 - 13279 (2021/05/10)
Controlling the reactivity of carbene intermediates is a key parameter in the development of selective carbene transfer reactions and is usually achieved by metal complexes via singlet metal-carbene intermediates. In this combined experimental and computational studies, we show that the reactivity of free diaryl carbenes can be controlled by the electronic properties of the substituents without the need of external additives. The introduction of electron-donating and -withdrawing groups results in a significant perturbation of singlet triplet energy splitting of the diaryl carbene intermediate and of activation energies of consecutive carbene transfer reactions. This strategy now overcomes a long-standing paradigm in the reactivity of diaryl carbenes and allows the realization of highly chemoselective carbene transfer reactions with alkynes. We could show that free diaryl carbenes can be readily accessed via photolysis of the corresponding diazo compounds and that these carbenes can undergo highly chemoselective cyclopropenation, cascade, or C?H functionalization reactions. Experimental and theoretical mechanistic analyses confirm the participation of different carbene spin states and rationalize for the observed reactivity.
Oxime Ether Synthesis through O-H Functionalization of Oximes with Diazo Esters under Blue LED Irradiation
Li, Qian,Cai, Bao-Gui,Li, Lei,Xuan, Jun
supporting information, p. 6951 - 6955 (2021/09/02)
A green and sustainable oxime ether formation method via the visible-light-promoted O-H functionalization of oximes with diazo esters is described. The reaction occurs under very mild conditions (catalyst- and additive-free) with a high yield and a high functional group tolerance. When the reaction was performed with a cyclic ether as the solvent (e.g., THF, 1,4-dioxane, tetrahydropyran, ect.), an interesting photochemical three-component reaction product was obtained in good yields.
Copper-Mediated Cross-Coupling of Diazo Compounds with Sulfinates
Wang, Qian,Liu, An,Wang, Yan,Ni, Chuanfa,Hu, Jinbo
supporting information, p. 6919 - 6924 (2021/09/11)
A copper-mediated cross-coupling reaction between a diazo compound and a sodium alkane(arene)sulfinate gives a sulfone as the product. This reaction proceeds under mild conditions and features excellent functional group compatibility. A wide range of sodium alkane(arene)sulfinates were successfully applied in this chemistry. Mechanistic studies revealed that the overall reaction efficiency of the sulfinates was in line with their nucleophilicity in this reaction.
Silver-Catalyzed N-H Functionalization of Aryl/Aryl Diazoalkanes with Anilines
He, Feifei,Empel, Claire,Koenigs, Rene M.
supporting information, p. 6719 - 6723 (2021/09/13)
Herein, we report on the N-H functionalization reaction of primary and secondary anilines with diaryldiazoalkanes using simple AgPF6 as catalyst. We demonstrated broad applicability in the reaction of diaryldiazoalkanes with different anilines (31 examples, up to 97% yield). Furthermore, we propose a possible reaction mechanism for the N-H functionalization.
