6750-98-7Relevant academic research and scientific papers
Enhancing Ligand-Free Fe-Catalyzed Aminocarbonylation of Alkynes by ZrF4
Huang, Zijun,Dong, Yanan,Li, Yudong,Makha, Mohamed,Li, Yuehui
, p. 5236 - 5240 (2019/09/03)
Zirconium fluoride was utilized to promote efficiently iron-catalyzed aminocarbonylation between alkynes and amines without the use of extra ligands. In particular, this new system is applicable to a wide range of amine and alkyne substrates affording α,β-unsaturated amides in good to excellent yields. Preliminary mechanistic studies reveal the activation model involving interactions of ZF4 with both iron catalyst and amine substrates.
Enantioselective Epoxidation of Electron-Deficient Alkenes Catalyzed by Manganese Complexes with Chiral N4 Ligands Derived from Rigid Chiral Diamines
Chen, Xiangning,Gao, Bao,Su, Yijin,Huang, Hanmin
, p. 2535 - 2541 (2017/08/16)
A series of tetradentate sp2N/sp3N hybrid chiral N4 ligands derived from rigid chiral diamines were synthesized, which enabled the first manganese-catalyzed enantioselective epoxidation of electron-deficient alkenes with hydrogen peroxide (H2O2) as an oxidant. The reaction furnishes enantiomerically pure epoxy amides, epoxy ketones as well as epoxy esters in good yields and excellent enantioselectivities (up to 99.9% ee) with lower catalyst loading. Preliminary studies on structure–activity relationship demonstrated that maintaining comparatively lower electron-donating ability of the sp3N and relatively higher electron-donating ability of sp2N of the N4 ligands is beneficial to getting higher activity and selectivity, thus providing us a new view to understand epoxidation with H2O2. (Figure presented.).
An efficient mechanochemical synthesis of amides and dipeptides using 2,4,6-trichloro-1,3,5-triazine and PPh3
Duangkamol, Chuthamat,Jaita, Subin,Wangngae, Sirilak,Phakhodee, Wong,Pattarawarapan, Mookda
, p. 52624 - 52628 (2015/06/25)
A rapid, facile, and efficient mechanochemical synthesis of amides from carboxylic acids has been developed through an in situ acid activation with 2,4,6-trichloro-1,3,5-triazine and a catalytic amount of PPh3. Under room temperature solvent-drop grinding of the reactants in the presence of an inorganic base, a variety of carboxylic acids including aromatic acids, aliphatic acids, and N-protected α-amino acids undergo amidation to afford amides in moderate to excellent yields. The method is also compatible with Fmoc, Cbz, and Boc protecting groups which yields protected optically active dipeptides without detectable racemization.
Catalytic role of PPh3 and its polymer bound analog in the amidation of carboxylic acids mediated by 2,4,6-trichloro-1,3,5-triazine
Duangkamol, Chuthamat,Jaita, Subin,Wangngae, Sirilak,Phakhodee, Wong,Pattarawarapan, Mookda
supporting information, p. 4997 - 5001 (2015/08/03)
Abstract The catalytic role of PPh3 and its polymer bound analog was investigated in the 2,4,6-trichloro-1,3,5-triazine (TCT) mediated amidation of carboxylic acids. In the presence of inorganic bases which were inert toward TCT, carboxylic acids rapidly reacted with amines to afford amides in good to excellent yields. The described method also enabled the synthesis of optically active protected dipeptides without racemization. Formation of triazinylphosphonium chloride during the PPh3 catalyzed acid activation was confirmed based on 31P NMR studies.
Significance of reagent addition sequence in the amidation of carboxylic acids mediated by PPh3 and I2
Wangngae, Sirilak,Duangkamol, Chuthamat,Pattarawarapan, Mookda,Phakhodee, Wong
, p. 25789 - 25793 (2015/10/20)
The outcome of the amidation reaction mediated by PPh3-I2 was found to be highly dependent on the addition sequence of the reagents. When triethylamine was subjected to a mixture containing PPh3, I2, and a carboxylic acid, acid anhydride was generated almost instantly, before treatment with an amine, presumably via an attack of carboxylate ion onto the acyl function of an acyloxyphosphonium salt. Nevertheless, when a PPh3-I2 mixture was treated with an amine, then a carboxylic acid, prior to adding the base, amide was rapidly formed in high yield with high chemoselectivity, most likely through an intermediate O,N-pentacoordinate phosphorane species as confirmed by ESI-MS technique.
Enhancing the scope of the Diels-Alder reaction through isonitrile chemistry: Emergence of a new class of acyl-activated dienophiles
Townsend, Steven D.,Wu, Xiangyang,Danishefsky, Samuel J.
, p. 10659 - 10663 (2012/08/08)
α,β-Unsaturated imides, formylated at the nitrogen atom, comprise a new and valuable family of dienophiles for servicing Diels-Alder reactions. These systems are assembled through extension of recently discovered isonitrile chemistry to the domain of α,β-unsaturated acids. Cycloadditions are facilitated by Et2AlCl, presumably via chelation between the two carbonyl groups of the N-formyl amide. Applications of the isonitrile/Diels-Alder logic to the IMDA reaction, as well as methodologies to modify the N-formyl amide of the resultant cycloaddition product, are described. It is expected that this easily executed chemistry will provide a significant enhancement for application of Diels-Alder reactions to many synthetic targets.
NHC-catalyzed C-O or C-N bond formation: Efficient approaches to α,β-unsaturated esters and amides
Zhang, Bo,Feng, Peng,Cui, Yuxin,Jiao, Ning
supporting information; experimental part, p. 7280 - 7282 (2012/07/28)
Simple and efficient NHC-catalyzed transformations of bromoenal or α,β-dibromoenal into α,β-unsaturated esters or amides with high stereoselectivity through C-O or C-N bond formation have been demonstrated. The NHC-catalyzed processes occur under mild con
Copper-catalyzed β-boration of α,β-unsaturated carbonyl compounds with tetrahydroxydiborane
Molander, Gary A.,McKee, Silas A.
supporting information; experimental part, p. 4684 - 4687 (2011/11/06)
The copper-catalyzed β-boration of α,β-unsaturated carbonyl compounds with tetrahydroxydiborane has been developed. This diboron reagent allows direct, efficient access to boronic acids and their derivatives. Primary, secondary, and tertiary α,β-unsaturated amides are converted to the corresponding β-trifluoroboratoamides in good to excellent yields. The β-boration of a variety of α,β-unsaturated esters and ketones is also reported.
A general and selective iron-catalyzed aminocarbonylation of alkynes: Synthesis of acryl- and cinnamides
Driller, Katrin Marie,Prateeptongkum, Saisuree,Jackstell, Ralf,Beller, Matthias
scheme or table, p. 537 - 541 (2011/03/16)
Entering the iron age: The first general method for iron-catalyzed monocarbonylation of alkynes has been developed. A range of structurally diverse cinnamides and acrylamides have been obtained smoothly starting from commercially available amines and alkynes in the presence of [Fe 3(CO)12] and ligand L (see scheme). The method is highly chemo- and regioselective and requires no expensive catalyst.
Samarium-mediated mild and facile method for the synthesis of amides
Shi, Feng,Li, Jian,Li, Chunju,Jia, Xueshun
experimental part, p. 6049 - 6051 (2010/11/21)
Samarium-mediated facile method for the formation of amide bonds by the reaction of acyl chlorides and amines is described. The reaction afforded high yields of the desired amides under mild and neutral conditions.
