2851-09-4

Usage

InChI:InChI=1/C12H14N2O/c1-4-8-14(9-5-1)12-13-10-6-2-3-7-11(10)15-12/h2-3,6-7H,1,4-5,8-9H2

Upstream product

• 110-89-4 piperidine 
• 4694-88-6 benzooxazole-2-sulfonic acid; potassium salt 
• 766-09-6 1-ethyl-piperidine 
• 615-18-9 2-chloro-1,3-benzoxazole 
• 2156-71-0 N-chloropiperidine 
• 273-53-0 benzoxazole 
• 95-55-6 2-amino-phenol 
• 2382-96-9 2-sulfanyl-1,3-benzoxazole 
• 59-49-4 2-Benzoxazolinone 
• 626-67-5 N-methylcyclohexylamine 
• 2591-86-8 N-Formylpiperidine 
• 5542-49-4 piperidin-1-yl benzoate 
• 102675-92-3 2-iodo-1,3-benzoxazole 
• 35856-62-3 1-piperidinesulfonyl chloride 

Relevant academic research and scientific papers

New topological Co2(BDC)2(DABCO) as a highly active heterogeneous catalyst for the amination of oxazoles via oxidative C-H/N-H couplings

Herein, we report the synthesis, structural characterization, and catalytic properties of a new cobalt-based metal-organic framework, Co2(BDC)2(DABCO) (where BDC = 1,4-benzenedicarboxylate and DABCO = 1,4-diazabicyclo[2.2.2]octane), namely VNU-10 (where VNU = Vietnam National University). Single-crystal X-ray diffraction analysis revealed that VNU-10 crystallizes in the hexagonal space group P6/mmm. The structure of this material is comprised of two-dimensional kgm layers which are interconnected by DABCO pillars to afford an overall three-dimensional porous architecture. VNU-10 exhibited exceptional catalytic activity toward the direct amination of oxazoles via C-H/N-H couplings while a previously reported topological isomer, Co2(BDC)2(DABCO), with the sql topology, displayed poor activity. Leaching tests indicated that homogeneous catalysis via leached active cobalt species is unlikely. Furthermore, the VNU-10 catalyst was facilely isolated from the reaction mixture and reused several times without degradation of the catalytic reactivity.

Room-Temperature Amination of Chloroheteroarenes in Water by a Recyclable Copper(II)-Phosphaadamantanium Sulfonate System

Buchwald-Hartwig amination of chloroheteroarenes has been a challenging synthetic process, with very few protocols promoting this important transformation at ambient temperature. The current report discusses about an efficient copper-based catalytic system (Cu/PTABS) for the amination of chloroheteroarenes at ambient temperature in water as the sole reaction solvent, a combination that is first to be reported. A wide variety of chloroheteroarenes could be coupled efficiently with primary and secondary amines as well as selected amino acid esters under mild reaction conditions. Catalytic efficiency of the developed protocol also promotes late-stage functionalization of active pharmaceutical ingredients (APIs) such as antibiotics (floxacins) and anticancer drugs. The catalytic system also performs efficiently at a very low concentration of 0.0001 mol % (TON = 980,000) and can be recycled 12 times without any appreciable loss in activity. Theoretical calculations reveal that the π-acceptor ability of the ligand PTABS is the main reason for the appreciably high reactivity of the catalytic system. Preliminary characterization of the catalytic species in the reaction was carried out using UV-VIS and ESR spectroscopy, providing evidence for the Cu(II) oxidation state.

Copper(ii) ions supported on functionalized graphene oxide: an organometallic nanocatalyst for oxidative amination of azolesviaC-H/C-N bond activation

Graphene oxide (GO) was chemically modified withpara-aminobenzoic acid (PABA) to immobilize copper(ii) ions on its surface and used as a nanocatalyst for the oxidative C(sp2)-H bond amination reaction. A practical method to prepare Cu2+supported onpara-aminobenzoic acid grafted on GO was reported. The prepared Cu2+@GO/PABA was characterized by FT-IR, XRD, SEM, AFM, TEM, UV-Vis, and ICP techniques. The results showed that the morphology, distribution, and loading of copper ions could be well-adjusted by grafting of PABA on GO. Moreover, just 2 mol% of Cu2+@GO-PABA could catalyze the C-H activation reaction of benzoxazole and benzothiazole with secondary amines in >94% yields. Also, the catalyst showed very good recyclability and much less leaching of the Cu into the reaction solution. The high activity of Cu2+@GO-PABA can be ascribed to the good synergistic effects of Cu2+andpara-aminobenzoic acid grafted on graphene oxide.

Zwitterionic Ring-Opened Oxyphosphonium Species from the Ph3P-I2 Mediated Reactions of Benzo[ d]oxazol-2(3 H)-ones with Secondary Amines

Instead of the expected substituted 2-aminobenzo[d]oxazoles, relatively stable ring-opened oxyphosphonium betaines were isolated for the first time from the Ph3P-I2-mediated reactions of benzo[d]oxazol-2(3H)-ones with acyclic seconda

CuII/H-USY as a regenerable bifunctional catalyst for the additive-free C-H amination of azoles

A copper-exchanged H-USY zeolite catalyst was developed for the direct C-H amination of azoles with secondary amines in HFIP. The reaction was performed under air without any external additive. The Cu/H-USY catalyst could be regenerated for further re-use without significant decrease in activity.

Metal-Free Synthesis of 2-N,N-Dialkylaminobenzoxazoles Using Tertiary Amines as the Nitrogen Source

The unprecedented reaction of tertiary amines with 2(3H)-benzoxazolones has been investigated. In the presence of the Ph3P-I2 reagent system, the reaction of both acyclic and cyclic aliphatic tertiary amines led to the formation of 2-N,N-dialkylaminobenzoxazoles with the selective cleavage of an alkyl group. Especially, N-(2-iodoethyl)piperazinyl derivatives were rapidly produced in good yields when using DABCO as the nitrogen source. Only in the cases when the nucleophilicity of the substrates exceeds that of the amine, competitive self-condensation of benzoxazolones then proceeds preferentially. 31P{1H}-NMR study suggested the involvement of an aryloxyphosphonium intermediate and/or possibly 2-iodobenzoxazole which activates the C-2 position of benzoxazolones toward nucleophilic aromatic substitution.

Dioxygen-triggered oxidative cleavage of the C-S bond towards C-N bond formation

Research on the cleavage of C-C bonds has been well developed. By comparison with this, the activation of C-S bonds remains challenging. Herein, dioxygen-triggered oxidative cleavage of C-S bonds has been achieved, delivering a series of N-containing heterocyclic compounds that are frequently found in pesticides and pharmaceuticals. Additionally, the potential utility of this protocol was further demonstrated by a gram-scale experiment. Mechanistically, dioxygen plays a key role in the cleavage of C-S bonds towards C-N bond formation.

Copper-Catalyzed Electrophilic Amination of Benzoxazoles via Magnesation

One-pot synthesis of 2-aminobenzoxazoles through copper-catalyzed electrophilic amination of benzoxazoles with O-benzoyl hydroxylamines is described. The direct magnesation of benzoxazoles with the readily available iPrMgCl generated benzoxazolylmagnesium reagents in situ and these reagents were treated with electrophilic amines in the presence of 10 mol-% Cu(OAc)2 and ZnCl2 under mild reaction conditions. A variety of 2-aminobenzoxazoles were obtained in good to excellent yields.

Hemoglobin: A New Biocatalyst for the Synthesis of 2-substituted Benzoxazoles via Oxidative Cyclization

Efficient and mild synthesis of a series of 2-substituted benzoxazoles via oxidative cyclization catalyzed by hemoglobins reported here for the first time. Satisfactory yields (84 %–97 %) and mild reaction conditions make this method highly viable for practical applications.

Pd/PTABS: Catalyst for Room Temperature Amination of Heteroarenes

A mild and highly efficient catalytic amination procedure for chloroheteroarenes at ambient temperature using the Pd/PTABS catalytic system is reported. The protocol is selective for the amination of chloroheteroarenes using secondary amines such as piperidine, pyrrolidine, and several others. The exceptional mildness of the developed protocol is beneficial for the synthesis of a crucial Buparlisib intermediate as well as the formal synthesis of Alogliptin in competitive yields.