40445-29-2Relevant academic research and scientific papers
Bio-heterogeneous Cu(0)NC@PHA for n-aryl/alkylation at room temperature
Jian Fui, Choong,Lutfor Rahman, Md,Musta, Baba,Sani Sarjadi, Mohd,Sarkar, Shaheen M.,Xin Ting, Tang
, (2021/06/28)
A pure cellulose was derived from waste fibre and it was chemically modified to a hydroxamic acid ligand. The poly(hydroxamic acid) was treated with an aqueous copper solution to afford the greenish stable five-membered copper complex; namely Cu(II)@PHA. Further, the Cu(II)@PHA was treated with a reducing agent hydrazine hydride to give brown colour cellulose supported copper nanocomplex (Cu(0)NC@PHA). The Cu(0)NC@PHA was characterised by ATR-FTIR, FE-SEM & EDS, TEM, ICP-OES, TGA, XRD and XPS analyses. The cellulose-based Cu(0)NC@PHA was used for the n-aryl/alkylation (Michael addition) reaction with a variety of α,β-unsaturated Michael acceptors to produce the corresponding n-aryl/alkyl products with an excellent yield at room temperature. The Cu(0)NC@PHA showed extraordinary stability and it was easily filtered out from the reaction mixture and may potentially recycled up to five times without loss of its original catalytic ability.
Cobalt(II)-catalyzed oxidative coupling of aromatic tertiary amines with enol silyl ethers leading to β-aminoketone derivatives
Sakai, Norio,Muraoka, Takuya,Matsumoto, Shun,Mutsuro, Akihiro,Ogiwara, Yohei
supporting information, p. 343 - 346 (2017/02/10)
We demonstrated that a cobalt(II)-TBHP (tert-butyl hydroperoxide) oxidizing system efficiently catalyzes the coupling of aromatic tertiary amines with enol silyl ethers, producing the corresponding β-aminoketones.
Aza-Michael reaction: Selective mono- versus bis-addition under environmentally-friendly conditions
Bosica, Giovanna,Spiteri, Jonathan,Borg, Caroline
, p. 2449 - 2454 (2014/04/03)
Aza-Michael reactions between primary amines and methyl propenoate have been investigated under environmentally-friendly solventless heterogeneous catalysis in order to obtain the mono- or the bis-adduct. The reaction conditions can be altered so as to maximise the yields of the required product with high selectivity.
Chemo/regioselective Aza-Michael additions of amines to conjugate alkenes catalyzed by polystyrene-supported AlCl3
Dai, Liyan,Zhang, Yi,Dou, Qianqian,Wang, Xiaozhong,Chen, Yingqi
, p. 1712 - 1716 (2013/03/13)
A simple and efficient procedure is presented for Aza-Michael additions of various amines with conjugate alkenes bearing electron withdrawing group catalyzed by polystyrene-supported aluminum chloride (Ps-AlCl3) without the use of any solvents. The catalyst shows high catalytic activity for both aromatic amines and aliphatic amines. Chemoselective additions of the two types of amines with conjugate alkenes are achieved. Regioselective additions of two different amino groups in one molecule proceed smoothly. Ps-AlCl 3 has better recyclability and can be reused several times without apparent loss of activity.
Synthesis and quantitative structure-activity relationship of imidazotetrazine prodrugs with activity independent of O6-methylguanine-DNA- methyltransferase, DNA mismatch repair, and p53
Pletsas, Dimitrios,Garelnabi, Elrashied A.E.,Li, Li,Phillips, Roger M.,Wheelhouse, Richard T.
, p. 7120 - 7132 (2013/10/01)
The antitumor prodrug temozolomide is compromised by its dependence for activity on DNA mismatch repair (MMR) and the repair of the chemosensitive DNA lesion, O6-methylguanine (O6-MeG), by O6-methylguanine-DNA-methyltransferase (E.C. 2.1.1.63, MGMT). Tumor response is also dependent on wild-type p53. Novel 3-(2-anilinoethyl)-substituted imidazotetrazines are reported that have activity independent of MGMT, MMR, and p53. This is achieved through a switch of mechanism so that bioactivity derives from imidazotetrazine-generated arylaziridinium ions that principally modify guanine-N7 sites on DNA. Mono- and bifunctional analogues are reported, and a quantitative structure-activity relationship (QSAR) study identified the p-tolyl-substituted bifunctional congener as optimized for potency, MGMT-independence, and MMR-independence. NCI60 data show the tumor cell response is distinct from other imidazotetrazines and DNA-guanine-N7 active agents such as nitrogen mustards and cisplatin. The new imidazotetrazine compounds are promising agents for further development, and their improved in vitro activity validates the principles on which they were designed.
Highly efficient nanocrystalline zirconosilicate catalysts for the aminolysis, alcoholysis, and hydroamination reactions
Kore, Rajkumar,Srivastava, Rajendra,Satpati, Biswarup
, p. 2891 - 2904 (2014/01/06)
Nanocrystalline zirconosilicates and titanosilicates with MFI framework structure were hydrothermally synthesized by the addition of organosilanes in the synthesis composition of conventional zirconosilicate and titanosilicate materials. Materials were characterized by a complementary combination of X-ray diffraction, nitrogen sorption, scanning/transmission electron microscopy (S/TEM), ammonia temperature-programmed desorption (TPD), Fourier transform infrared (FT-IR) spectroscopy, and ultraviolet-visible (UV-vis) spectroscopic investigations. Nanocrystalline zeolite catalysts of the present study are reusable. They exhibit significantly higher catalytic activities in aminolysis and alcoholysis compared with the hitherto known catalysts. A range of β-amino alcohols/β-alkoxy alcohols with high regioselectivity were synthesized using zirconosilicates. Application of these materials was also extended in the synthesis of aminoesters by the hydroamination reaction of methyl acrylates and amines. Structure activity relationship was explained based on acidity measurements, reactivity of amines/alcohols, and adsorption of reactants on catalysts.
Folding of alternating dialkylsilylene-spaced donor-acceptor copolymers: The oligomer approach
Chen, Chih-Hsien,Chen, Wen-Hao,Liu, Yi-Hung,Lim, Tsong-Shin,Luh, Tien-Yau
scheme or table, p. 347 - 354 (2012/03/09)
A series of oligmers with donor-acceptor pairs separated by diisopropylsilylene (iPr2Si) spacers, composed of monomer 4b, dimer 5, trimer 6, and tetramer 7, were synthesized to scrutinize the folding behavior. Monomer 4a with a dimethylsilylene (Me2Si) spacer was also prepared for comparison. The 4-aminostyrene moiety was used as the donor and the stilbene moiety as the acceptor. Both steady-state and time-resolved fluorescence spectroscopic measurement were made. Regardless of the substituents on the silicon atom, the emission spectra of 4a and 4b exhibit both local excited (LE) emission of the acceptor chromophore and emission from the charge-separated state (CT emission), which are similar to that of the corresponding Me2Si-spaced copolymer 2a with the same donor and acceptor chromophores, but different from that of the copolymer with the iPr2Si spacer 2b. Dimer 5 behaves like 4 and 2a. As the chain length of the oligomers increases, the emission properties of the higher homologues become prone to that of 2b. Thus, tetramer 7 exhibits emission from the charge-transfer complex, which is essentially same as that of 2b. Moreover, charge-transfer absorptions emerge in 6 and 7. These results suggest that the folding nature of oligomers approaches that of the corresponding polymer, as the degree of oligomerization increases, and the electronic interactions between adjacent donor-acceptor pairs are controlled by the steric effect of the substituents on the silicon atoms and concomitant amplification of the stabilizing energy by extending the distance of the folding structure. Copyright
Functionalized ionic liquid promoted aza-michael addition of aromatic amines
Liu, Xiao-Bing,Lu, Ming,Lu, Ting-Ting,Gu, Guo-Liang
experimental part, p. 1221 - 1226 (2011/10/02)
A functionalized ionic liquid, 3-(N,N-dimethyldodecylammonium) propanesulfonic acid hydrogen sulphate ([DDPA][HSO4]) has been used as catalyst for the aza-Michael reactions of aromatic amines with α,β-unsaturated compounds at room temperature to produce β-amino compounds in good yields. The catalyst can be reused for several times without obvious loss of the catalytic activity.
Supported cobalt complex-catalysed conjugate addition of indoles, amines and thiols to α,β-unsaturated compounds
Rajabi, Fatemeh,Razavi, Sepideh,Luque, Rafael
experimental part, p. 786 - 789 (2010/09/05)
A highly active and reusable supported Co(ii) complex on SBA-15 shows an excellent activity and selectivity to target products in aza- and thia-Michael conjugate additions of indoles, amines and thiols to α,β-unsaturated compounds under solventless mild reaction conditions. The Co-catalyst was also highly reusable and comparably more active than related catalysts in the reaction.
