27153-17-9Relevant articles and documents
Acid-catalyzed chemodivergent reactions of 2,2-dimethoxyacetaldehyde and anilines
Guo, Luxia,Chen, Zihao,Zhu, Hongmei,Li, Minghao,Gu, Yanlong
supporting information, p. 1419 - 1422 (2020/11/12)
Chemodivergent reactions of 2,2-dimethoxyacetaldehyde and anilines were described, which were established on the basis of either a C[sbnd]C bond cleavage or a rearrangement process of a reaction intermediate. These reactions proceeded in a condition-determined manner with good functional group tolerance. In the first model, 2,2-dimethoxyacetaldehyde reacted with aniline to form a new C[sbnd]N bond, in the presence of O2, via a C[sbnd]C bond cleavage reaction. However, in the second model, by performing the reaction in the absence of O2, Heyns rearrangement occurred and generated a new C[sbnd]O bond to form methyl phenylglycinate. Such condition-determined reactions not only offered the new way for value-added conversion of biomass-derived platform molecule, 2, 2-dimethoxyacetaldehyde, but also provided efficient methods for the synthesis of N-arylformamides and methyl phenylglycinates.
Selective: N-formylation/N-methylation of amines and N-formylation of amides and carbamates with carbon dioxide and hydrosilanes: Promotion of the basic counter anions of the zinc catalyst
Zhang, Qiao,Lin, Xiao-Tao,Fukaya, Norihisa,Fujitani, Tadahiro,Sato, Kazuhiko,Choi, Jun-Chul
supporting information, p. 8414 - 8422 (2020/12/29)
A catalyst composed of commercially available Zn(OAc)2 and 1,10-phenanthroline (phen) was effective in the N-formylation/N-methylation of amines using CO2 as the C1 source in the presence of hydrosilanes. An equimolar reaction of N-methylaniline with PhSiH3 under a CO2 atmosphere yielded the N-formylation product in 92% yield at 25 °C. Scale-up of the reaction using 10 mmol substrate was also successful in affording the desired product in 83% yield (1.1 g). This catalyst exhibits a high thermal stability and a turnover number (TON) of 385000 at 150 °C. In addition, the reaction of N-methylaniline in the presence of excess Ph2SiH2 produced N,N-dimethylaniline. Furthermore, our catalytic protocol was developed for the N-formylation of amides and carbamates, which have smaller pKa values and lower reactivities than the corresponding amines. The present Zn(OAc)2/phen catalyst was found to show versatility in the conversion of CO2 and amines into several functionalized organic chemicals under mild conditions. We propose that the basic counter anion (i.e., the acetate) of the catalyst activates both the Si-H and N-H bonds.
L-Serine?ZnO as an efficient and reusable catalyst for synthesis of cyclic carbonates and formamides in presence of CO2 atmosphere
Ahire, Jayendra P.,Bhanage, Bhalchandra M.,Phatake, Vishal V.
, (2020/06/03)
The highly efficient carbon dioxide (CO2) fixation into value-added organic carbonates has gained enormous attention in the last few decades. This work reports, synthesis and characterization of amino acids (AAs) assisted ZnO nano catalyst and Its application for the cyclic carbonates and formamides synthesis with CO2 atmosphere. The prepared catalysts are characterized by IR, SEM, TEM, XRD, DSC-TGA XPS analysis. L-Serine?ZnO exhibits excellent catalytic activity for transformation of CO2 into value-added chemicals namely formamides and cyclic carbonates. The catalytic systems which work in the presence of CO2 balloon atmosphere for the synthesis of cyclic carbonates are rarely explored. This catalytic system shows excellent activity under the CO2 balloon atmosphere for carbonate synthesis. The developed methodology demonstrates broad substrate scope as well as excellent functional group tolerance for carbonates and formamides synthesis. Additionally, the synthesized catalyst was recyclable up to five recycling runs without considerable loss in its catalytic activity, thus makes this protocol cost-effective and sustainable.