622-16-2Relevant articles and documents
Synthesis, Structure, and Photophysical Properties of Mo2(NN)4 and Mo2(NN)2(TiPB)2, Where NN = N,N′-Diphenylphenylpropiolamidinate and TiPB = 2,4,6-Triisopropylbenzoate
Jiang, Changcheng,Young, Philip J.,Durr, Christopher B.,Spilker, Thomas F.,Chisholm, Malcolm H.
, p. 5836 - 5844 (2016)
Two dimolybdenum compounds featuring amidinate ligands with a bond, Mo2(NN)4 (I), where NN = N,N′-diphenylphenylpropiolamidinate, and trans-Mo2(NN)2(TiPB)2 (II), where TiPB = 2,4,6-triisopropylbenzoate, have been prepared and structurally characterized by single-crystal X-ray crystallography. Together with Mo2(DAniF)4 (III), where DAniF = N,N′-bis(p-anisyl)formamidinate, all three compounds have been studied with steady-state UV-vis, IR, and time-resolved spectroscopy methods. I and II display intense metal to ligand charge transfer (MLCT). Singlet state (S1) lifetimes of I-III are determined to be 0.7, 19.1, and 2.0 ps, respectively. All three compounds have long-lived triplet state (T1) lifetimes around 100 μs. In femtosecond time-resolved infrared (fs-TRIR) experiments, one band is observed at the S1 state for I but two for II, which indicate different patterns of charge distribution. The electron would have to be localized on one NN ligand in I and partially delocalized over two NN ligands in II to account for the observations. The result is a standard showcase of excited-state mixed valence in coordination compounds.
Probing Interligand Electron Transfer in the 1MLCT S1 Excited State of trans-Mo2L2L′2 Compounds: A Comparative Study of Auxiliary Ligands and Solvents
Jiang, Changcheng,Young, Philip J.,Brown-Xu, Samantha E.,Kender, William T.,Hamilton, Ewan J. M.,Gallucci, Judith C.,Chisholm, Malcolm H.
, p. 9660 - 9668 (2017)
The interligand charge dynamics of the lowest singlet metal-to-ligand charge-transfer states (1MLCT S1 states) of a series of quadruply bonded trans-Mo2(NN)2(O2C-X)2 paddlewheel compounds are investigated, where NN is a π-accepting phenylpropiolamidinate ligand and O2C-X (X = Me, tBu, TiPB, or CF3) is an auxiliary carboxylate ligand. The compounds show strong light absorption in the visible region due to MLCT transitions from the Mo2 center to the NN ligands. The transferred electron density was followed by femtosecond time-resolved infrared (fs-TRIR) spectroscopy with vibrational reporters such as the ethynyl groups on the NN ligands. The observed fs-TRIR spectra show that these compounds have asymmetric 1MLCT S1 excited states where the transferred electron mainly resides on a single NN ligand. The presence of interligand electron transfer (ILET) is suggested to explain the shape of the ν(C=C) bands and the influence of auxiliary ligands and solvents on the interligand electronic coupling. The ILET in the 1MLCT S1 state is shown to be sensitive to the functional groups on the auxiliary ligands while being less responsive to changes in solvents.
Synthesis of 1,4-diphenyl-3-phenylimino-1,2-dihydro-1,2,4-triazolium hydroxide (nitron)
Kriven'ko,Morozova
, p. 506 - 507 (2006)
1,4-Diphenyl-3-phenylimino-1,2-dihydro-1,2,4-triazolium hydroxide (Nitron) is prepared by the reaction of Pb3O4 with diphenylthiourea, followed by the reaction of the obtained diphenylcarbodiimide with phenylhydrazine to form triphenylaminoguanidine, whose heterocyclization yields 1,4-diphenyl-3-phenyl-imino-1,2-dihydro-1,2,4-triazole, which is subsequently oxidized. Pleiades Publishing, Inc., 2006.
Synthesis and Properties of N,N′-Disubstituted Ureas and Their Isosteric Analogs Containing Polycyclic Fragments: XI. 1-[(Adamantan-1 yl)alkyl]-3-arylselenoureas
Kuznetsov, Ya. P.,Rasskazova,Pitushkin,Eshtukov,Vasipov,Burmistrov,Butov
, p. 1036 - 1046 (2021/09/08)
Abstract: A series of N,N′-disubstituted selenoureas containing an adamantane fragmenthave been synthesized in 23–75% yields. Procedures for the isolation andpurification of aromatic isoselenocyanates have been improved. The chemicalshift of the C=Se carbon nucleus in the 13C NMRspectra of selenoureas has been refined. The synthesized selenoureas have beenfound to be promising as inhibitors of not only epoxide hydrolase (sEH-H) butalso phosphatase domains (sEH-P) of human soluble epoxide hydrolase.
A Mild Photocatalytic Synthesis of Guanidine from Thiourea under Visible Light
Saetan, Trin,Sukwattanasinitt, Mongkol,Wacharasindhu, Sumrit
supporting information, p. 7864 - 7869 (2020/11/02)
In this work, we developed the catalytic guanylation of thiourea using Ru(bpy)3Cl2 as a photocatalyst under irradiation by visible light. The conversion of various thioureas to the corresponding guanidines was achieved using 1-5 mol % of photocatalyst in a mixture of water and ethanol at room temperature. Key benefits of this reaction include the use of photoredox catalyst, low-toxicity solvents/base, ambient temperature, and an open-flask environment.
Synthesis of 1,2,4-oxadiazolidines via [3+2] cycloaddition of nitrones with carbodiimides
Chen, Yuan,Fuyue, Liuting,Wang, Gangqiang,Wang, Hang,Lu, Chun,Guo, Haibing,St. Amant, Chiara,Sun, Shaofa,Xing, Yalan
supporting information, p. 4329 - 4332 (2019/03/19)
An efficient [3+2] cycloaddition of nitrones and carbodiimides has been developed. This 1,3-dipolar cycloaddition features high regioselectivity, mild and metal-free conditions, excellent functional group compatibility, and a broad substrate scope. The X-ray structures of two regio-isomers confirmed the regioselectivity of this transformation.
A facile method for the preparation of carbodiimides from thioureas and (Boc)2O
Wu, He,Sun, Yan-Fang,Zhang, Chen,Miao, Chun-Bao,Yang, Hai-Tao
supporting information, p. 739 - 742 (2018/01/27)
A concise method for the preparation of carbodiimides from thioureas using di-tert-butyl dicarbonate [(Boc)2O] as the dehydrosulfurizative reagent has been developed. Using DMAP as the catalyst, a variety of symmetric and asymmetric 1,3-diaryl thioureas were converted into the corresponding carbodiimides efficiently in a short time.
Copper-catalyzed domino reaction of carbodiimides and benzoic acid derivatives for the synthesis of quinazolinediones
Duangjan, Chanikan,Rukachaisirikul, Vatcharin,Saithong, Saowanit,Kaeobamrung, Juthanat
supporting information, p. 3537 - 3540 (2018/08/29)
Quinazolinediones were obtained from 2-iodobenzoic acids and carbodiimide derivatives under mild reaction conditions via a copper-catalyzed domino reaction. The absence of an external base was essential to avoid the generation of amide by-products. Both alkyl- and aryl-substituted carbodiimides gave the corresponding quinazolinediones. However, the use of aryl-substituted carbodiimides resulted in low yields due to an undesired elimination process.
RE[N(SiMe3)2]3-Catalyzed Guanylation/Cyclization of Amino Acid Esters and Carbodiimides
Lu, Chengrong,Gong, Chao,Zhao, Bei,Hu, Lijuan,Yao, Yingming
, p. 1154 - 1159 (2018/02/10)
The example of rare-earth metal-catalyzed guanylation/cyclization of amino acid esters and carbodiimides is well-established, forming 4(3H)-2-alkylaminoquinazolinones in 65-96% yields. The rare-earth metal amides RE[N(TMS)2]3 (RE = Y, Yb, Nd, Sm, La; TMS = SiMe3) showed high activities, and La[N(TMS)2]3 performed best for a wide scope of the substrates.
Sequential Pd(0)/Fe(III) Catalyzed Azide-Isocyanide Coupling/Cyclization Reaction: One-Pot Synthesis of Aminotetrazoles
Pathare, Ramdas S.,Ansari, Arshad J.,Verma, Sarika,Maurya, Anand,Maurya, Antim K.,Agnihotri, Vijai K.,Sharon, Ashoke,Pardasani, Ram T.,Sawant, Devesh M.
supporting information, p. 9530 - 9537 (2018/08/03)
A rapid and efficient synthesis of aminotetrazole from aryl azides, isocyanides, and TMSN3 is developed. The reaction is promoted by sequential Pd(0)/Fe(III) catalysis. The reaction sequence utilizes the Pd-catalyzed azide-isocyanide denitrogenative coupling reaction to generate unsymmetric carbodiimide in situ, which reacts with TMSN3 in the presence of FeCl3 in a single pot. The methodology has distinct advantages over traditional synthetic approaches where toxic Hg and Pb salts are employed at stoichiometric scale.
