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1.
A novel organocatalytic asymmetric reductive amination of aldehydes has been developed. Treating racemic alpha-branched aldehydes with p-anisidine and a Hantzsch ester in the presence of our previously developed phosphoric acid catalyst, TRIP, gave beta-branched secondary amines in excellent yields and enantioselectivities via an efficient dynamic kinetic resolution. The process is applicable to several different aromatic aldehydes and amines but gives slightly reduced enantiomeric ratios with aliphatic aldehydes. 相似文献
2.
A facile method for the direct synthesis of amides from aldehydes is described. Amide bonds were synthesized by an oxidative amidation in the presence of dibromoisocyanuric acid (DBI). Treatment of aromatic and aliphatic aldehydes with dibromoisocyanuric acid generated acyl bromide intermediates, which were employed to react with a variety of secondary and primary amines to give amides. Through this reaction method, various amides were synthesized directly from aldehydes under mild conditions in high yields and short times. This facile and efficient procedure provides potential strategy for the direct synthesis of amides from aldehydes. 相似文献
3.
4.
A. N. Rodionov A. A. Simenel Yu. S. Nekrasov V. V. Kachal E. Yu. Osipova K. Ya. Zherebker 《Russian Chemical Bulletin》2010,59(2):405-410
1-Aryl-3-ferrocenyl-4-formylpyrazoles were obtained from appropriate acetylferrocene arylhydrazones by the Vilsmeier—Haack
reaction. Direct reductive amination of the resulting aldehydes with primary and secondary amines and amino acid esters in
the presence of NaBH(OAc)3 was studied. 相似文献
5.
Abdel-Magid AF Carson KG Harris BD Maryanoff CA Shah RD 《The Journal of organic chemistry》1996,61(11):3849-3862
Sodium triacetoxyborohydride is presented as a general reducing agent for the reductive amination of aldehydes and ketones. Procedures for using this mild and selective reagent have been developed for a wide variety of substrates. The scope of the reaction includes aliphatic acyclic and cyclic ketones, aliphatic and aromatic aldehydes, and primary and secondary amines including a variety of weakly basic and nonbasic amines. Limitations include reactions with aromatic and unsaturated ketones and some sterically hindered ketones and amines. 1,2-Dichloroethane (DCE) is the preferred reaction solvent, but reactions can also be carried out in tetrahydrofuran (THF) and occasionally in acetonitrile. Acetic acid may be used as catalyst with ketone reactions, but it is generally not needed with aldehydes. The procedure is carried out effectively in the presence of acid sensitive functional groups such as acetals and ketals; it can also be carried out in the presence of reducible functional groups such as C-C multiple bonds and cyano and nitro groups. Reactions are generally faster in DCE than in THF, and in both solvents, reactions are faster in the presence of AcOH. In comparison with other reductive amination procedures such as NaBH(3)CN/MeOH, borane-pyridine, and catalytic hydrogenation, NaBH(OAc)(3) gave consistently higher yields and fewer side products. In the reductive amination of some aldehydes with primary amines where dialkylation is a problem we adopted a stepwise procedure involving imine formation in MeOH followed by reduction with NaBH(4). 相似文献
6.
Heshmatollah Alinezhad Mahmood Tajbakhsh Fatemeh Salehian 《Monatshefte für Chemie / Chemical Monthly》2005,43(9):2029-2033
A variety of aliphatic and aromatic aldehydes and ketones were efficiently reduced to their corresponding amines when treated
with primary and secondary amines and NaBH4 in micellar media at room temperature under neutral conditions. 相似文献
7.
Summary. A variety of aliphatic and aromatic aldehydes and ketones were efficiently reduced to their corresponding amines when treated
with primary and secondary amines and NaBH4 in micellar media at room temperature under neutral conditions. 相似文献
8.
Bogdan Boduszek Tomasz Olszewski Waldemar Goldeman Magdalena Konieczna 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):787-795
The synthesis of a series of new pyridine aminomethylphosphinic acids is described. These compounds were obtained in the reaction of the corresponding pyridine aldehydes with primary amines and with ethyl phenylphosphinate, or methylphosphinate, in the presence of bromotrimethylsilane. In aqueous, strong acid solutions, pyridine aminophosphinic acids were split, forming the phenyl-, or methylphosphonic, acid and the corresponding secondary pyridyl-alkylamines. The kinetics of some observed cleavages were measured, and a mechanism of the cleavage has been proposed. 相似文献
9.
P. Veeraraghavan Ramachandran Pravin D. Gagare Paul Clark 《Tetrahedron letters》2010,51(24):3167-4082
A variety of primary, secondary, and tertiary amines were prepared in 84-95% yields using ammonia borane for the reductive amination of aldehydes and ketones in the presence of titanium isopropoxide. 相似文献
10.
Danwei Pi Haifeng Zhou Yanmei Zhou Qixing Liu Renke He Guanshuo Shen Yasuhiro Uozumi 《Tetrahedron》2018,74(17):2121-2129
A ligand-free copper-catalyzed reduction of azaarenes with diboronic acid as reductant in an aprotic solvent under mild conditions has been developed. Most interestingly, the nitroazaarenes could be reduced exclusively to give the corresponding amines without touching the azaarene moieties. Furthermore, the reductive amination of aromatic nitro compounds and aromatic aldehydes has also been realized. A series of hydrogenated azaarenes and secondary amines were obtained with good functional group tolerance. 相似文献
11.
Reductive amination of aromatic aldehydes takes place when treated with equimolar amounts of aromatic amines and NADH model compounds in glacial acetic acid. Imines, the intermediates in the reaction were also reduced by NADH models in acetic acid. 相似文献
12.
Gurusamy Harichandran Savarimuthu David Amalraj Ponnusamy Shanmugam 《Journal of Saudi Chemical Society》2018,22(2):208-217
A one-pot Amberlite IRA-400 Cl resin catalyzed the in-situ generation of imines from various aldehydes and primary amines followed by reduction with sodium borohydride affording corresponding secondary amines. The secondary amines thus obtained were utilized for the IRA-400 Cl resin catalyzed multicomponent synthesis of 3-aminoalkylated indoles using a number of aldehydes and indole. Mild condition, easy work-up, and environmentally benign nature of the synthetic strategy make it both practical and attractive. 相似文献
13.
The solid-phase synthesis of a 4500-member (30 x 15 x 10) tyrphostin library is demonstrated utilizing the Irori-directed sorting system. Fmoc-protected PL-Rink resin was used as the solid support. After Fmoc-deprotection, aryl aldehydes were attached to the resin through reductive amination. Acylation of the resulting secondary amines with cyanoacetic acid was followed by a Knoevenagel condensation with phenolic aldehydes. Mitsunobu coupling of primary alcohols to the resin-bound phenols yielded the final library of compounds 1. 相似文献
14.
One Pot Reduction of Imines Generated in-situ from Aldehydes and Amines by the NaBH4-InCl3 System 总被引:1,自引:0,他引:1
A combination of sodium borohydride and a catalytic amount of indium(Ⅲ) chloride in acetonitrile reduces imines formed in-situ from aldehydes and amines to the corresponding functionalised secondary and tertiary amines in moderate to good yields. Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogens, carbon-carbon double bonds and hydroxyl groups. 相似文献
15.
André Robichaud 《Tetrahedron letters》2006,47(22):3633-3636
An unprecedented efficient and highly selective direct reductive amination of aldehydes with primary and secondary amines in water using gaseous hydrogen and water-soluble catalysts is developed. The catalytic system formed in situ from Pd(PhCN)2Cl2 and 2,2′-biquinoline-4,4′-dicarboxylic acid dipotassium salt (BQC), allows full conversion of aldehydes and the formation of desired alkylated amines with excellent yields and selectivities. The catalytic system is stable and can be recycled and reused three times without loss of activity. 相似文献
16.
A simple and efficient method has been developed for the synthesis of α-aminophosphinic acids from hypophosphorus acid under solvent-free conditions using microwave irradiation. α-Aminophosphinic acids were obtained in high yield under mild conditions by reaction of hypophosphorus acid with aldehydes in the presence of amines under microwave irradiation. 相似文献
17.
Wei Su Ya Xie Ming Chen Zhenmin Xu Da Shi Prof. Weiguo Yu Prof. Feng Jiang Prof. Han Yu 《欧洲无机化学杂志》2023,26(16):e202200751
Secondary and tertiary amine derivatives are very important in chemical and pharmaceutical industries. The N-alkylation of amines with aldehydes is a proper way to form secondary and tertiary amines. However, the traditional catalyst systems for this transformation bring a series of problems such as narrow substrate scope, challenges of difficult catalyst preparation and metal residues and toxicity. Herein an efficient way to perform N-alkylation of amines with aldehydes was described which used a molecular Mo oxide catalyst. In this pathway, various aldehyde and amine derivatives were successfully converted to the corresponding secondary and tertiary amines with high selectivity and efficiency. In addition, the catalyst was easy to prepare, and could be recycled six times without appreciable loss of conversion. Finally, the reaction mechanism was presented based on the observation of the possible intermediates and control experiments. 相似文献
18.
Chang Min Chih‐Tsung Lin Prof. Dr. Daniel Seidel 《Angewandte Chemie (International ed. in English)》2015,54(22):6608-6612
A readily available chiral Brønsted acid was identified as an efficient catalyst for intramolecular Povarov reactions. Polycyclic amines containing three contiguous stereogenic centers were obtained with excellent stereocontrol in a single step from secondary anilines and aldehydes possessing a pendent dienophile. These transformations constitute the first examples of catalytic enantioselective intramolecular aza‐Diels–Alder reactions. 相似文献
19.
[Structure: see text] Syn-configured aldol products of mandelic acid esters and aldehydes were synthesized by the catalytic use of amines in the presence of titanium(IV) tert-butoxide. Used along with chiral N-methylephedrine, anti-configured alpha,beta-dihydroxyesters were isolated with a high degree of enantioselectivity for the first time. 相似文献
20.
[chemical reaction: see text]. An improved procedure for the direct reductive amination of aldehydes was developed which uses dibutyltin dichloride as catalyst in the presence of phenylsilane as reductant. Rapid reaction is promoted by the use of microwave conditions with anilines, secondary and primary amines being suitable reactants. 相似文献