5626-53-9Relevant academic research and scientific papers
Hydroamination and Hydrophosphination of Isocyanates/Isothiocyanates under Catalyst-Free Conditions
Zhu, Xiancui,Xu, Mengchen,Sun, Jinrong,Guo, Dianjun,Zhang, Yiwei,Zhou, Shuangliu,Wang, Shaowu
, p. 5213 - 5218 (2021/10/19)
Symmetrical and unsymmetrical N,N’-disubstituted as well as trisubstituted ureas/thioureas by the hydroamination of isocyanates/isothiocyanates, and various phosphathioureas by the hydrophosphination of isothiocyanates have been synthesized in good to excellent yields under catalyst-free and mild conditions. This protocol is also applicable for the efficient synthesis of chiral ureas and thioureas and common herbicides, such as fenuron and monuron.
Catalyst-free solventless synthesis of polysubstituted urea Method for preparing thioureas and chiral ureas and thiourea compounds
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Paragraph 0056-0062; 0098-0104, (2021/09/29)
The invention discloses a method for synthesizing polysubstituted urea, thiourea and chiral urea and thiourea compounds without catalyst without solvent, and the method comprises A contact reaction of an amine compound with a structure shown B as shown first in a non-catalyst and a solventless condition to prepare a polysubstituted urea or thiourea compound with a structure as shown C. R1 And R2 Each independently selected from a hydrocarbyl or substituted hydrocarbyl group, R3 The method is selected from H, hydrocarbyl or substituted hydrocarbyl, X is S or o. The method solves the defect that a catalyst and/or a solvent need to be used in the synthesis of urea and thiourea compounds in the prior art.
Lanthanum(III) Trifluoromethanesulfonate Catalyzed Direct Synthesis of Ureas from N-Benzyloxycarbonyl-, N -Allyloxycarbonyl-, and N -2,2,2-Trichloroethoxycarbonyl-Protected Amines
Bui, Tien Tan,Kim, Hee-Kwon
supporting information, p. 997 - 1002 (2020/06/17)
A novel lanthanum triflate mediated conversion of N -benzyloxycarbonyl-, N -allyloxycarbonyl-, and N -trichloroethoxycarbonyl-protected amines into nonsymmetric ureas was discovered. In this study, lanthanum triflate was found to be an effective catalyst for preparing various nonsymmetric ureas from protected amines. A variety of protected aromatic and aliphatic carbamates reacted readily with various amines in the presence of lanthanum triflate to generate the desired ureas in high yields. This result demonstrated that this novel lanthanum triflate catalyzed preparation of ureas from Cbz, Alloc, and Troc carbamates can be employed for the formation of various urea structures.
Method for preparing asymmetric urea compound (by machine translation)
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Paragraph 0043-0048; 0049-0054, (2020/03/25)
The invention provides a vehicle CO. 2 A method. for synthesizing an asymmetric urea compound by carbonylation coupling reaction of the carbonylation reagent is: and the aromatic, aliphatic primary amine compound and the aliphatic secondary amine compound and the normal pressure (100 °C, diglyme), can be efficiently prepared by using a common Lewis base and a hydrogen silane as the accelerator/CO under mild conditions. 2 The reaction produces a corresponding asymmetric urea compound. containing different functional groups, the process being operated at atmospheric pressure CO. 2 The use of an inexpensive Lewis base and, industrial silicon waste PMHS( for the green non-toxic carbonylation reagent) avoids toxic carbonylation reagents, high pressure, as an accelerator CO. 2 , The use, of the expensive dehydrating agent and the noble metal does not need to purify and separate the intermediate, and the pure product, is obtained by simple suction filtration separation after the reaction is ended . is a high efficiency, novel synthetic method . The commercial herbicide NEBURON. is successfully prepared by using the method. (by machine translation)
CaI2-Catalyzed direct transformation of: N -Alloc-, N -Troc-, and N -Cbz-protected amines to asymmetrical ureas
Tran, Van Hieu,Kim, Hee-Kwon
, p. 14093 - 14101 (2019/09/18)
A novel and facile CaI2-catalyzed direct synthesis of asymmetrical ureas from N-Alloc-, N-Troc-, and N-Cbz-protected amines is developed. In this study, the efficient reaction of Alloc-, Troc-, and Cbz-carbamates with amines in the presence of catalytic CaI2 successfully generated various asymmetrical ureas. This catalytic synthetic procedure provided the desired ureas via reactions of these protected aromatic and aliphatic amines with various amines in high yields without side products. This suggests that novel direct synthesis of ureas from Alloc-, Troc-, and Cbz-carbamates can be a promising approach for the synthesis of useful ureas.
2-Picolylamino(diphenylphosphinoselenoic)amide supported zinc complexes: Efficient catalyst for insertion of N–H bond into carbodiimides, isocyanates, and isothiocyanate
Harinath, Adimulam,Bano, Kulsum,Ahmed, Shakil,Panda, Tarun K.
supporting information, p. 23 - 32 (2017/09/25)
We report here the hydroamination of heterocumulenes such as carbodiimides, isocyanates, and isothiocyanates by zinc complexes supported by the ligand 2-picolylamino-(diphenylphosphinoselenoic)amide [{(Ph2P-(?Se)}2NCH2(C5H4N)] (1). A series of zinc complexes [κ2-{(Ph2P-(?Se)}2NCH2(C5H4N)ZnX2] [(X?Cl (2), Br (3a), I (4)] were prepared from ligand 1 and the corresponding zinc dihalide in a 1:1 molar ratio at 60°C in a chloroform solvent. The reaction of ligand 1 and ZnBr2 in methanol yielded another zinc complex [κ2-{(Ph2P-(?Se)}2NCH2(C5H4N)ZnBr2(CH3OH)] (3b). The molecular structures of compounds 3a, 3b, and 4 were established through single-crystal X-ray diffraction analyses. The solid-state structures of all the complexes revealed a κ2- chelation through pyridine nitrogen and selenium atoms of ligand 1 to the zinc ion. Complex 2 proved to be a competent pre-catalyst for the addition of the amine N–H bond to carbodiimides, isocyanates, and isothiocyanates. The reaction scope was expanded to reactions of aliphatic and aromatic amines with phenylisocyanate and phenylisothiocyanate in toluene solvents, which proceeded rapidly at room temperature with 5 mol% catalyst loading to yield (up to 99%) the corresponding derivatives of urea and thio-urea. However, a temperature of 90°C was needed for the hydroamination of N,N′ dicyclohexylcarbodiimide. We also report the most plausible mechanism of the hydroamination reaction.
Synthesis of ureas in the bio-alternative solvent Cyrene
Mistry, Liam,Mapesa, Kopano,Bousfield, Thomas W.,Camp, Jason E.
supporting information, p. 2123 - 2128 (2017/07/24)
Cyrene as a bio-alternative solvent: a highly efficient, waste minimizing protocol for the synthesis of ureas from isocyanates and secondary amines in the bio-available solvent Cyrene is reported. This method eliminated the use of toxic solvents, such as
Hydroamination of carbodiimides, isocyanates, and isothiocyanates by a bis(phosphinoselenoic amide) supported titanium(IV) complex
Bhattacharjee, Jayeeta,Das, Suman,Kottalanka, Ravi K.,Panda, Tarun K.
supporting information, p. 17824 - 17832 (2016/11/18)
The hydroamination of heterocumulenes such as carbodiimides, isocyanates, and isothiocyanates by a bis(phosphinoselenoic amide) supported titanium(iv) complex as a precatalyst is reported here. The titanium(iv) complex [{Ph2P(Se)NCH2CH2NPPh2(Se)}Ti(NMe2)2] (1) was synthesised by the reaction of tetrakis-(dimethylamido)titanium(iv) [Ti(NMe2)4] with [{Ph2P(Se)NHCH2CH2NHPPh2(Se)}] in toluene at ambient temperature. Titanium complex 1 proved to be a competent pre-catalyst for the addition of an amine N-H bond to carbodiimides, isocyanates, and isothiocyanates. The reaction scope was expanded to reactions of aliphatic and aromatic amines with phenylisocyanates and phenylisothiocyanates in toluene solvents proceeding rapidly at room temperature with 5 mol% catalyst loadings to yield the corresponding urea and thio-urea derivatives up to 99%. However, ambient temperature was needed for hydroamination of 1,3-dicyclohexylcarbodiimide. The amine addition reactions with isocyanates showed first order kinetics with respect to catalyst 1 as well as substrates. The most plausible mechanism for the hydroamination reaction was established by isolating 1,1-dimethylphenyl urea as a side product.
Zinc catalyzed Guanylation reaction of Amines with Carbodiimides/ Isocyanate leading to Guanidines/Urea derivatives formation
Bhattacharjee, Jayeeta,Sachdeva, Mitali,Banerjee, Indrani,Panda, Tarun K
, p. 875 - 881 (2016/07/06)
We report the highly chemo-selective catalytic addition of N–H bonds from various aromatic amines to carbodiimides and isocyanates using (Ar-BIAO)ZnCl2 complexes [Ar-BIAO = N-(aryl)imino-acenapthenone, Ar = 2,6-Me2C6H3 (1), 2,4,6 Me3C6H2 (2), 2,6-iPr2C6H3 (3)] as the pre-catalyst to prepare guanidine and urea derivatives in 55-90% yield. The complex 3 showed higher catalytic activity than analogous complexes 1 and 2 under similar reaction conditions. The catalytic guanylation of N–H bonds with heterocumulenes displays a broad substrate scope. The amines having electron donating groups underwent higher conversion than the amines having electron withdrawing groups to afford corresponding guanidine or urea derivatives. A possible mechanism involving penta-coordinated zinc transition state for the catalytic reaction is presented. [Figure not available: see fulltext.]
Imidazolin-2-iminato Ligand-Supported Titanium Complexes as Catalysts for the Synthesis of Urea Derivatives
Naktode, Kishor,Das, Suman,Bhattacharjee, Jayeeta,Nayek, Hari Pada,Panda, Tarun K.
supporting information, p. 1142 - 1153 (2016/02/09)
The reactions of tetrakis(dimethylamido)titanium(IV) [Ti(NMe2)4] with three different imidazolin-2-imines (ImRNH; R = tert-butyl (tBu), mesityl (Mes), and 2,6-diisopropylphenyl (Dipp)) afforded the corresponding titanium i
