136551-45-6Relevant academic research and scientific papers
Enantioselective Hydroamination of Alkenes with Sulfonamides Enabled by Proton-Coupled Electron Transfer
Demaerel, Joachim,Graff, David E.,Knowles, Robert R.,Roos, Casey B.
supporting information, p. 5974 - 5979 (2020/04/27)
An enantioselective, radical-based method for the intramolecular hydroamination of alkenes with sulfonamides is reported. These reactions are proposed to proceed via N-centered radicals formed by proton-coupled electron transfer (PCET) activation of sulfonamide N-H bonds. Noncovalent interactions between the neutral sulfonamidyl radical and a chiral phosphoric acid generated in the PCET event are hypothesized to serve as the basis for asymmetric induction in a subsequent C-N bond forming step, achieving selectivities of up to 98:2 er. These results offer further support for the ability of noncovalent interactions to enforce stereoselectivity in reactions of transient and highly reactive open-shell intermediates.
Trimethylsilyl-Induced N-O Bond Cleavage in Nitrous Oxide-Derived Aminodiazotates
Liu, Yizhu,Eymann, Léonard Y. M.,Solari, Euro,Fadaei Tirani, Farzaneh,Scopelliti, Rosario,Severin, Kay
supporting information, p. 11859 - 11863 (2018/09/25)
The chemical activation of nitrous oxide (N2O) typically results in O-atom transfer and the extrusion of N2 gas. In contrast, reactions of N-trimethylsilyl (TMS)-substituted amides with N2O give inorganic or organic azides
Organo-Cation Catalyzed Asymmetric Homo/Heterodialkylation of Bisoxindoles: Construction of Vicinal All-Carbon Quaternary Stereocenters and Total Synthesis of (-)-Chimonanthidine
Chen, Si-Kai,Ma, Wen-Qiang,Yan, Zhi-Bo,Zhang, Fu-Min,Wang, Shao-Hua,Tu, Yong-Qiang,Zhang, Xiao-Ming,Tian, Jin-Miao
supporting information, p. 10099 - 10103 (2018/08/23)
A novel chiral spirocyclic amide (SPA)-derived triazolium organocatalyst has been designed and demonstrated to effect asymmetric homo- and heterodialkylations of various bisoxindoles, enabling enantioselective construction of vicinal all-carbon quaternary stereocenters. These reactions feature excellent enantio- and diastereoselectivities (up to 99% ee and >20:1 dr) as well as good to high yields (up to 89% over two steps). As an application of this methodology, the first asymmetric total synthesis of (-)-chimonanthidine has been achieved.
Phosphino-Triazole Ligands for Palladium-Catalyzed Cross-Coupling
Zhao, Yiming,Van Nguyen, Huy,Male, Louise,Craven, Philip,Buckley, Benjamin R.,Fossey, John S.
supporting information, p. 4224 - 4241 (2018/10/25)
Twelve 1,5-disubtituted and fourteen 5-substituted 1,2,3-triazole derivatives bearing diaryl or dialkyl phosphines at the 5-position were synthesized and used as ligands for palladium-catalyzed Suzuki-Miyaura cross-coupling reactions. Bulky substrates wer
Modular Synthesis of Triazole-Based Chiral Iodoarenes for Enantioselective Spirocyclizations
Hempel, Christian,Maichle-M?ssmer, Caeciliea,Pericàs, Miquel A.,Nachtsheim, Boris J.
, p. 2931 - 2941 (2017/09/06)
A new triazole-based C1-symmetrical chiral iodoarene was synthesized in a highly modular route. Based on enzymatic kinetic resolution of an easily accessible propargylic alcohol both enantiomers were accessible in enantiopure form. By Huisgen-type azide-alkyne cycloaddtion a series of differently substituted iodoarenes was synthesized in high overall yields. Finally this novel iodoarene was successfully applied in the oxidative Kita cyclization of naphthol derivatives. Good yields and high ee values were obtained in the asymmetric spirocyclization via in situ generation of the hypervalent iodine species using mCPBA as the terminal oxidant. (Figure presented.).
Ruthenium Bisammine Complex and Its Reaction with Aryl Azides
Park, Jin Yong,Kim, Yongjin,Bae, Dae Young,Rhee, Young Ho,Park, Jaiwook
supporting information, p. 3471 - 3476 (2017/10/03)
A ruthenium bisammine complex was formed in the reaction of ruthenium 1,4-dibenzyltetraazadiene complex with primary amines at room temperature, which was a versatile precursor for the synthesis of various Ru(II) complexes through ligand exchange reactions. In the reaction with azidobenzene, ruthenium 1,4-diphenyltetraaza-1,3-diene complex was formed, while ruthenium imido complexes were given in the reaction with bulky aryl azides such as 2-azido-1,3-dimethylbenzene and 2-azido-1,3-diisopropylbenzene. The ruthenium imido complexes showed high catalytic activity in the reaction of alkyl azides with primary amines to afford N-substituted imines.
'Click' generated 1,2,3-triazole based organosulfur/selenium ligands and their Pd(II) and Ru(II) complexes: Their synthesis, structure and catalytic applications
Kumar, Satyendra,Saleem, Fariha,Singh, Ajai K.
, p. 11445 - 11458 (2016/07/26)
1-(2,6-Diisopropylphenyl)-4-(phenylthio/selenomethyl)-1H-1,2,3-triazole (L1/L2) was synthesized by a 'Click' reaction and treated with [Pd(CH3CN)2Cl2] for 5 h or [(η6-C6H6)RuCl(μ-Cl)]2 for 8 h (followed by reaction with NH4PF6) at room temperature, resulting in complexes [Pd(L)Cl2] (1 and 2) or [(η6-C6H6)Ru(L)Cl]PF6 (3 and 4) (L = L1 or L2), respectively. The four complexes (1-4) and ligands (L1 and L2) were characterized with 1H, 13C{1H} and 77Se{1H} NMR spectroscopy and high resolution mass spectrometry. The single crystal structures of 1-4 were solved. The geometry of Pd in 1 and 2 is distorted square planar. The Pd-S and Pd-Se bond distances in 1 and 2 are 2.277(3) and 2.384(6) ? respectively. In 3 and 4, there is a pseudo-octahedral "piano-stool" type disposition of donor atoms around Ru. The Ru-S and Ru-Se bond lengths in 3 and 4 are 2.3728(12) and 2.4741(6) ? respectively. The catalytic activity of complexes 1 and 2 was explored for Suzuki-Miyaura coupling (SMC) in water and the Sonogashira coupling reaction. For various aryl bromides, including deactivated ones, complexes 1 and 2 were found to be efficient catalysts for both couplings. The optimum loading of 1 and 2 required to catalyze both coupling reactions is of the order of 0.001-2 mol% of Pd. For SMC, no additive or phase transfer catalyst was added. For catalysis of the transfer hydrogenation (TH) of aldehydes and ketones, the half-sandwich Ru(ii) complexes 3 and 4 were explored. Their optimum catalytic loading was found to be 0.1-0.4 mol% of Ru. For TH, both the water solvent and the glycerol hydrogen source are environmentally friendly. The catalytic efficiencies of 3 and 4 are comparable with those reported for other catalysts for TH carried out with 2-propanol or glycerol as a H-source. 1, with a sulfur ligand, is more efficient than 2 (Se analog) for both SMC and the Sonogashira coupling. The activities of 3 and 4 for TH are in the order Se > S.
Phosphoramidate tantalum complexes for room-temperature C-H functionalization: Hydroaminoalkylation catalysis
Garcia, Pierre,Lau, Ying Yin,Perry, Mitchell R.,Schafer, Laurel L.
supporting information, p. 9144 - 9148 (2013/09/12)
A cooled reaction: Phosphoramidate-ClTaMe3 complexes promote the first example of room-temperature hydroaminoalkylation catalysis. This reaction can be realized under solvent-free conditions and with challenging substrates such as styrenes and dialkyl amines. When using a vinylsilane substrate, for the first time the linear regioisomer is obtained preferentially using a Group5 metal. TBS=tert-butyldimethylsilyl, TMS=trimethylsilyl. Copyright
Redox-active triazolium-derived ligands in nucleophilic fe-catalysis - Reactivity profile and development of a regioselective o-allylation
Klein, Johannes E. M. N.,Holzwarth, Michael S.,Hohloch, Stephan,Sarkar, Biprajit,Plietker, Bernd
supporting information, p. 6310 - 6316 (2013/10/21)
Triazolium-derived N-heterocyclic carbene (aNHC) ligands, which are readily accessible by deprotonation of the corresponding triazolium salts, proved to be versatile ligands in diverse allylic substitution reactions. The corresponding triazolium salts are formed from azides and alkynes through the application of 1,3-dipolar cycloaddition and N-alkylation reactions. The unique property of these ligands is to be zwitterionic in their liberated form and to act as strong redox-active σ-donor ligands. By virtue of these qualities, these ligands enable the development of an unprecedented Fe-catalyzed regioselective aryloxylation of allylic carbonates. Copyright
Suzuki-Miyaura cross-coupling reaction catalyzed by PEPPSI-type 1,4-di(2,6-diisopropylphenyl)-1,2,3-triazol-5-ylidene (tzIPr) palladium complex
Huang, Jie,Hong, Jong-Tai,Hong, Soon Hyeok
, p. 6630 - 6635 (2013/01/15)
A 1,4-di(2,6-diisopropylphenyl)-1,2,3-triazol-5-ylidene (tzIPr)-based PEPPSI-type palladium complex was developed as an excellent precatalyst for the Suzuki-Miyaura cross-coupling reaction. The complex showed high activity under mild conditions for the cross-coupling reactions between various types of aryl chlorides and aryl boronic acids regardless of the steric and electronic nature of the substrates.
