- Contrasting behavior in azide pyrolyses: An investigation of the thermal decompositions of methyl azidoformate, ethyl azidoformate and 2-azido-N, N-dimethylacetamide by ultraviolet photoelectron spectroscopy and matrix isolation infrared spectroscopy
-
The thermal decompositions of methyl azidoformate (N3COOMe), ethyl azidoformate (N3COOEt) and 2-azido-N,N-dimethylacetamide (N3CH2-CONMe2) have been studied by matrix isolation infrared spectroscopy and real-time ultraviolet photoelectron spectroscopy. N2 appears as an initial pyrolysis product in all systems, and the principal interest lies in the fate of the accompanying organic fragment. For methyl azidoformate, four accompanying products were observed: HNCO, H2CO, CH2NH and CO2, and these are believed to arise as a result of two competing decomposition routes of a four-membered cyclic intermediate. Ethyl azidoformate pyrolysis yields four corresponding products: HNCO, MeCHO, MeCHNH and CO2, together with the five-membered-ring compound 2-oxazolidone. In contrast, the initial pyrolysis of 2-azido-N,N-dimethyl acetamide, yields the novel imine intermediate Me2NCOCH=NH, which subsequently decomposes into dimethyl formamide (HCONMe2), CO, Me2NH and HCN. This intermediate was detected by matrix isolation IR spectroscopy, and its identity confirmed both by a molecular orbital calculation of its IR spectrum, and by the temperature dependence and distribution of products in the PES and IR studies. Mechanisms are proposed for the formation and decomposition of all the products observed in these three systems, based on the experimental evidence and the results of supporting molecular orbital calculations.
- Dyke, John M.,Levita, Giacomo,Morris, Alan,Ogden, J. Steven,Dias, Antonio A.,Algarra, Manolo,Santos, Jose P.,Costa, Maria L.,Rodrigues, Paula,Andrade, Marta M.,Barros, M. Teresa
-
-
Read Online
- Visible-Light-Induced Multicomponent Synthesis of γ-Amino Esters with Diazo Compounds
-
A visible-light-induced multicomponent reaction of ethyl diazoacetate, diarylamines, and styrene-type alkenes is described. This novel 1,2-difunctionalization of alkenes can be readily achieved under a simple operation and mild conditions, affording γ-amino esters as major products. The reaction proceeds through the generation of carbon-centered radicals from diazo compounds by a visible-light-promoted proton-coupled electron transfer (PCET) process. The carbon radicals then add to diverse alkenes, delivering new carbon radical species, and the final products are formed with N-centered radicals via a radical-radical coupling.
- Ma, Na,Guo, Lin,Qi, Dan,Gao, Fei,Yang, Chao,Xia, Wujiong
-
supporting information
p. 6278 - 6282
(2021/08/30)
-
- Nucleophilic Iron Complexes in Proton-Transfer Catalysis: An Iron-Catalyzed Dimroth Cyclocondensation
-
The nucleophilic iron complex Bu4N[Fe(CO)3(NO)] (TBA[Fe]) is an active catalyst in C?H-amination but also in proton-transfer catalysis. Herein, we describe the successful use of this complex as a proton-transfer catalyst in the cyclocondensation reaction between azides and ketones to the corresponding 1,2,3-triazoles. Cross-experiments indicate that the proton-transfer catalysis is significantly faster than the nitrene-transfer catalysis, which would lead to the C?H amination product. An example of a successful sequential Dimroth triazole–indoline synthesis to the corresponding triazole-substituted indolines is presented.
- Baykal, Aslihan,Zhang, Dihan,Knelles, Jakob,Alt, Isabel T.,Plietker, Bernd
-
supporting information
p. 3003 - 3010
(2019/08/21)
-
- Copper(I)-Catalyzed Synthesis of 1,4-Disubstituted 1,2,3-Triazoles from Azidoformates and Aryl Terminal Alkynes
-
The copper(I)-catalyzed azide-alkyne cycloaddition reaction has been extensively studied and widely applied in organic synthesis. However, the formation of 1,2,3-triazoles with electron-deficient azide has been a challenging problem. In this report, we ha
- Lee, Heejin,Lee, Jae Kyun,Min, Sun-Joon,Seo, Hyeonglim,Lee, Youngbok,Rhee, Hakjune
-
p. 4805 - 4811
(2018/04/26)
-
- Iridium(III)-Catalyzed Regiocontrolled Direct Amidation of Isoquinolones and Pyridones
-
Iridium(III)-catalyzed highly regiocontrolled C3/C8 amidation of isoquinolones and C6 amidation of 2-pyridones has been successfully accomplished with various azides. The optimized method is operationally simple with a broad substrate scope. The protocol has been found to be scalable. (Figure presented.).
- Das, Debapratim,Samanta, Rajarshi
-
supporting information
p. 379 - 384
(2017/12/26)
-
- Spin-selective generation of triplet nitrenes: Olefin aziridination through visible-light photosensitization of azidoformates
-
Azidoformates are interesting potential nitrene precursors, but their direct photochemical activation can result in competitive formation of aziridination and allylic amination products. Herein, we show that visible-light-activated transition-metal comple
- Scholz, Spencer O.,Farney, Elliot P.,Kim, Sangyun,Bates, Desiree M.,Yoon, Tehshik P.
-
supporting information
p. 2239 - 2242
(2016/02/18)
-
- A solvent-free amidation of vinylogous esters via direct aziridination
-
A microwave-mediated aziridination of α,β-unsaturated ketones and esters through the decomposition of ethyl azidoformate has been developed. When the same atom-economical reaction conditions are applied to cyclic vinylogous esters, N-functionalization at
- McLaughlin, Emily C.,Shrestha, Anuska,Fletcher, Madison H.,Steinauer, Nathaniel S.,Shinn, Min Kyung,Shahid, Sabrina M.
-
p. 5461 - 5463
(2013/09/23)
-
- Functionalization of single-walled carbon nanotubes with (R-)oxycarbonyl nitrenes
-
Sidewall functionalization of single-walled carbon nanotubes (SWCNTs) via the addition of (R-)-oxycarbonyl nitrenes allows for the covalent binding of a variety of different groups such as alkyl chains, aromatic groups, dendrimers, crown ethers, and oligoethylene glycol units. Such additions lead to a considerable increase in the solubility in organic solvents such as 1,1,2,2-tetrachloroethane (TCE), dimethyl sulfoxide (DMSO), and 1,2-dichlorobenzene (ODCB). The highest solubilities of 1.2 mg/mL were found for SWCNT adducts with nitrenes containing crown ether of oligoethylene glycol moieties in DMSO and TCE, respectively. The presence of chelating donor groups within the addends allowed for the complexation of Cu2+ and Cd2+. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) revealed that the functionalized tubes form thin bundles with typical diameters of 10 nm. The presence of thin bundles in solution is supported by 1H NMR spectroscopy. The elemental composition of the functionalized SWCNT was determined by X-ray photoelectron spectroscopy (XPS). The use of Raman and electron absorption spectroscopy (UV/Vis-nIR) showed that the electronic properties of the SWCNTs are mostly retained after functionalization, indicating a low degree of addition within this series of SWCNT derivatives.
- Holzinger, Michael,Abraham, Juergen,Whelan, Paul,Graupner, Ralf,Ley, Lothar,Hennrich, Frank,Kappes, Manfred,Hirsch, Andreas
-
p. 8566 - 8580
(2007/10/03)
-
- Asymmetric synthesis of N-(ethoxycarbonyl)-β-methylphenylalanine esters
-
Amination of the silyl ketene acetal of methyl (R)-3-phenylbutanoate (3) by photolysis with ethyl azidoformate gave the derivative of (2R,3S)-β-methylphenylalanine (4) with a low diastereomeric excess in spite of the resident chirality. Using the silyl ke
- Fioravanti,Loreto,Pellacani,Sabbatini,Tardella
-
p. 473 - 478
(2007/10/02)
-
- A PARTICULARLY CONVENIENT ONE-POT SYNTHESIS OF N-ALKOXYCARBONYL, N-ACYL AND N-AROYL SUBSTITUTED IMINOPHOSPHORANES; IMPROVED PREPARATION OF AZIDOFORMATES, AROYL AND ALKANOYL AZIDES; AN ALTERNATIVE ROUTE TO COMPLEX AMIDES
-
Chloroformates and acid chlorides react smoothly with sodium azide in acetone at 0 deg C, forming azidoformates, aroyl and alkanoyl azides in very high yield.With triphenylphosphine or other phosphines present in the reaction mixture, the forming azides are intercepted, leading directly to the corresponding N-alkanoyl, N-aroyl, N-alkoxycarbonyl, and N-aryloxycarbonyliminophosphoranes.N-acyliminophosphoranes react with n-butyllithium forming anions which react readily with electrophiles, e.g., carbonyl compounds, forming highly substituted iminophosphoranes.The phosphonium group is effortlessly removed from the latter compounds by acid hydrolysis forming the corresponding amides in high yield.Key words: Synthesis; iminophosphoranes; aroyl azides; alkanoyl azides; complex amides.
- Froeyen, Paul
-
p. 161 - 172
(2007/10/02)
-
- Ester of (triarylphosphoranylidene)carbamic acid having diuretic and ability to lower plasma renin properties
-
Novel triarylphosphinimide derivatives having the formula STR1 wherein R1, R2 and R3 are each at the ortho or meta position, represent mono- or disubstituents and are selected from the group consisting of hydrogen, alkyl(C1 -C3), alkoxy(C1 -C3), trifluoromethyl and halogen; and R4 is selected from the group consisting of alkyl(C1 -C3), alkenyl(C2 -C3), alkynyl(C2 -C4), cycloalkyl(C3 -C5), cycloalkyl(C3 -C6)methyl, 4-oxopentyl, 3-tetrahydrofuranyl, 2,3-dihydro-1H-inden-1-yl, 1-alkyl(C1 -C3)cyclopentyl, trans-2-alkyl(C1 -C3)cyclopentyl, trans-2-alkoxy(C1 -C3)cyclopentyl, 1-cyclopropylethyl, 2-methylcyclopropylmethyl, dicyclopropylmethyl, 2-, 3- or 4-pyridinylmethyl, 2-cyclopenten-1-yl, tetrahydro-2H-pyran-4-yl and cis and trans-2-methoxycyclohexyl; with the proviso that when R4 is alkyl(C1 -C3), R1, R2 and R3 may not each be hydrogen STR2 wherein R1, R2 and R3 are each at the ortho or meta position and are selected from hydrogen and alkyl(C1 -C3), and X is an acid addition salt; processes for producing them, compositions containing them, and methods for using them in mammals to effect diuresis; to lower plasma renin levels and to increase cardiac contractility.
- -
-
-
- Azides. Part IV. Thermolysis of ethyl azidoformate in dimethyl terephthalate; formation of a diazabicyclooctadiene heterocycle
-
Thermal decomposition of ethyl azidoformate in excess of dimethyl terephthalate (DMT) (1) in acetic anhydride as solvent results in the formation of N,N-dicarbethoxy-4,8-dicarbomethoxy-2,6-diazabicycloocta-3,7-diene (3) in addition to N-carbethoxy-2,5-dicarbomethoxy-1H-azepine (2) and ethyl-N-(2,5-dicarbomethoxyphenyl)carbamate (4).The structure of the diazabicyclooctadiene (3) was established on the basis of spectral, elemental, and X-ray crystallographic analyses.
- Ayyangar, N. R.,Bambal, R. B.,Srinivasan, K. V.,Row, T. N. Guru,Puranik, V. G.,et al.
-
p. 1969 - 1973
(2007/10/02)
-
- Reaction of 1,1-Disubstituted Hydrazines with Diethyl Azodicarboxylate
-
The reaction of hydrazine derivatives 1 with diethyl azodicarboxylate (2) gives primarily the aminonitrenes 3, which add to the azodicarboxylate 2 forming the instable aminoazimines 7.These decompose by rearrangement to urethanes 8 and azidoformic acid ester 9.Furthermore the tetrazenes 5 are formed.The amount of 5 depends on the reaction conditions.
- Fahr, Egon,Koch, Karl-Heinz
-
p. 219 - 222
(2007/10/02)
-
- Oil-soluble aziridinyl urea compounds as lubricating oil detergents
-
Novel compositions are prepared from the thermal decomposition product of azidoformate esters reacting with aliphatic hydrocarbon olefins to form aziridine carbamates, which are then reacted with a polyamine free of primary amino groups and having at least one secondary amino group. These compositions find use as detergents and dispersants in lubricating oils and fuels, and also as emulsifiers.
- -
-
-