2601-10-7Relevant articles and documents
Synthesis of multifunctional polymer containing Ni-Pd NPs via thiol-ene reaction for one-pot cascade reactions
Javad Kalbasi, Roozbeh,Mesgarsaravi, Niloofar,Gharibi, Reza
, (2019/02/03)
Recently, acid–base bifunctional catalysts have been considered due to their abilities, such as the simultaneous activation of electrophilic and nucleophilic species and their high importance in organic syntheses. However, the synthesis of acid–base catalysts is problematic due to the neutralization of acidic and basic groups. This work reports a facial approach to solve this problem via the synthesis of a novel bifunctional polymer using inexpensive materials and easy methods. In this way, at the first step, heterogeneous poly (styrene sulfonic acid-n-vinylimidazole) containing pentaerythritol tetra-(3-mercaptopropionate) (PETMP) and trimethylolpropane trimethacrylate (TMPTMA) cross-linkers were synthesized in the pores of a mesoporous silica structure using click reaction as a novel bifunctional acid–base catalyst. After that, Ni-Pd nanoparticles supported on poly (styrenesulfonic acid-n-vinylimidazole)/KIT-6 as a novel trifunctional heterogeneous acid–base-metal catalyst was prepared. The prepared catalysts were characterized by various techniques like FT-IR, TGA, ICP-AES, DRS-UV, TEM, FE-SEM, EDS-Mapping, and XRD. The synthesized catalysts were efficiently used as bifunctional/trifunctional catalysts for one-pot, deacetalization-Knoevenagel condensation and one-pot, three-step and a sequential reaction containing deacetalization-Knoevenagel condensation-reduction reaction. It is important to note that the synthesized catalyst showing high chemo-selectivity for the reduction of nitro group, alkenyl double bond and ester group in the presence of nitrile. Moreover, it was found that the different nanoparticles including Ni, Pd, and alloyed Ni-Pd showing different chemo-selectivity and catalytic activity in the reaction.
Cobalt(II) chloride hexahydrate-diisopropylamine catalyzed mild and chemoselective reduction of carboxylic esters with sodium borohydride
Jagdale, Arun R.,Paraskar, Abhimanyu S.,Sudalai, Arumugam
experimental part, p. 660 - 664 (2009/07/03)
The cobalt-catalyzed reduction of unsaturated α-cyano carboxylic esters using sodium borohydride (NaBH4) leads to the corresponding saturated cyano alcohols in high yields. In particular, the new catalytic system cobalt(II) chloride-diisopropylamine in combination with NaBH4 showed excellent activity in the chemoselective reduction of a variety of carboxylic esters to their corresponding alcohols in good to excellent yields under mild conditions. Georg Thieme Verlag Stuttgart.
Optimization of 1H-tetrazole-1-alkanenitriles as potent orally bioavailable growth hormone secretagogues
Hernandez, Andres S.,Swartz, Stephen G.,Slusarchyk, Dorothy,Yan, Mujing,Seethala, R. Krishna,Sleph, Paul,Grover, Gary,Dickinson, Kenneth,Giupponi, Leah,Harper, Timothy W.,Humphreys, W. Griffith,Longhi, Daniel A.,Flynn, Neil,Murphy, Brian J.,Gordon, David A.,Biller, Scott A.,Robl, Jeffrey A.,Tino, Joseph A.
, p. 2067 - 2072 (2008/12/21)
1H-Tetrazole-1-alkanenitrile SR-9g exhibits a >10-fold in vivo potency enhancement over the lead nitrile 1 and has acceptable oral bioavailability in rats and dogs. An enantiospecific synthesis of 1H-tetrazole-1-alkanenitrile nitriles 9 has been developed.
Nitrile biotransformations for the synthesis of enantiomerically enriched β2-, and β3-hydroxy and -alkoxy acids and amides, a dramatic O-substituent effect of the substrates on enantioselectivity
Ma, Da-You,Wang, De-Xian,Pan, Jie,Huang, Zhi-Tang,Wang, Mei-Xiang
, p. 322 - 329 (2008/09/19)
Rhodococcus erythropolis AJ270, a nitrile hydratase/amidase-containing microbial whole cell catalyst, is able to catalyze the hydrolysis of a number of β-hydroxy and β-alkoxy nitriles under very mild conditions. Both the efficiency and enantioselectivity of the biocatalysis, however, were strongly dependent upon the structures of both nitrile and amide substrates. When biotransformations of racemic 3-hydroxy-3-phenylpropionitrile and 2-hydroxymethyl-3-phenylpropionitrile gave low enantioselectivity, their O-methylated isomers underwent highly efficient and enantioselective biocatalytic reactions to afford highly enantioenriched β2- and β3-hydroxy amide and acid derivatives in excellent yield. The study has provided an example of simple and very convenient substrate engineering method to increase the enantioselectivity of the biocatalytic reaction.
Methods and compositions for treating amyloid-related diseases
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Page/Page column 170-171, (2010/11/24)
Methods, compounds, pharmaceutical compositions and kits are described for treating or preventing amyloid-related disease.
Nitrile biotransformations for the practical synthesis of highly enantiopure azido carboxylic acids and amides, 'click' to functionalized chiral triazoles and chiral β-amino acids
Ma, Da-You,Wang, De-Xian,Zheng, Qi-Yu,Wang, Mei-Xiang
, p. 2366 - 2376 (2007/10/03)
Under very mild conditions, biotransformations of racemic azido nitriles using Rhodococcus erythropolis AJ270, a nitrile hydratase/amidase-containing microbial whole-cell catalyst, afforded highly enantiopure, (R)-α-arylmethyl- and (+)-α-cyclohexylmethyl-β-azidopropanoic acids and their (S)- and (-)-carboxamide derivatives in excellent yields. The resulting functionalized chiral organoazides were converted in a straightforward fashion to a pair of antipodes of α-benzyl-β-amino acids (R)-13 and (S)-13. Azido carboxamide (S)-11a and azido carboxylic acid (R)-12a underwent 'click' reactions with diethyl acetylenedicarboxylate and phenylacetylene to produce functionalized chiral triazoles 14 and 15, respectively. The easy preparation of the starting nitrile substrates, highly efficient and enantioselective biotransformation reactions, and versatile utility of the resulting functionalized azido carboxylic acids and amide derivatives, render this method very attractive and practical in organic synthesis.
