531-67-9Relevant articles and documents
-
Forostyan et al.
, (1972)
-
Optical Resolution of DL-2,2'-Bipiperidine through its Cobalt(III) Complex
Sato, Mitsunobu,Sato, Yoichi,Yano, Shigenobu,Yoshikawa, Sadao
, p. 895 - 898 (1985)
The separation of racemic 2,2'-bipiperidine and the meso form has been performed through the dihydrochloride salt of the diamine.The reaction of racemic 2,2'-bipiperidine with 2)6>3- has been shown to yield only one DL pair of trans-bis(2,2'-bipiperidine)dinitrocobalt(III) complex ion.The dinitro-complex has been characterized and optically resolved using ammonium D-2-bromo-4,7-dimethyl-3-oxobicycloheptane-7-methanesulphonate.Optically pure (-)589-2,2'-bipiperidine was recovered from the less soluble diastereoisomer and shows a specific rotation of -12.2 deg.The stereoselective formation of the trans-dinitro-complex is discussed in relation to the predictions of strain energy minimization calculations.
Cu ion-exchanged and Cu nanoparticles decorated mesoporous ZSM-5 catalysts for the activation and utilization of phenylacetylene in a sustainable chemical synthesis
Sarmah, Bhaskar,Satpati, Biswarup,Srivastava, Rajendra
, p. 87066 - 87081 (2016/09/23)
Mesoporous ZSM-5 was synthesized using a 1,4-diazabicyclo[2.2.2]octane based multi-cationic surfactant as a structure directing agent. Cu2+ exchanged mesoporous ZSM-5 was prepared by the ion-exchange process. Cu nanoparticles decorated mesoporous ZSM-5 was prepared using NaBH4 as a reducing agent. Materials were characterized by the complementary combination of X-ray diffraction, N2-adsorption, UV-visible, and scanning/transmission electron microscopic techniques. For comparative purposes, Cu2+ exchanged ZSM-5, HY, and NaY; and Cu nanoparticles decorated conventional ZSM-5, SBA-15, and Al2O3 samples were also prepared. A sustainable catalytic process was developed for the selective synthesis of indolizine, chalcone, and triazole derivatives using a mesoporous ZSM-5 based heterogeneous catalyst. A multi-component synthetic strategy is reported here for the selective synthesis of the above mentioned chemicals that involves phenylacetylene as one of the building blocks. Control experiments were performed to ascertain the proposed reaction pathways. Recycling and leaching experiments were performed to demonstrate the sustainability and robustness of the catalytic process. Among these catalysts, Cu nanoparticles decorated mesoporous ZSM-5 exhibited the highest activity in all these reactions. The catalyst was found to be highly stable and it was possible to recycle the catalyst five times with no appreciable loss in the activity. A wide range of indolizine, chalcone, and 1,2,3-triazole derivatives were prepared in high yields using this catalyst.
Chiral phosphoramide-catalyzed enantioselective addition of allylic trichlorosilanes to aldehydes. Preparative studies with bidentate phosphorus-based amides
Denmark, Scott E.,Fu, Jiping,Lawler, Michael J.
, p. 1523 - 1536 (2007/10/03)
On the basis of the mechanistic insight that more than one Lewis basic moiety (phosphoramide) is involved in the rate- and stereochemistry-determining step of enantioselective allylation, bidentate chiral phosphoramides were developed. Different chiral phosphoramide moieties were connected by tethers of methylene chains of varying length. The rate and enantioselectivity of allylation with allyltrichlorosilane promoted by the bidentate phosphoramides was found to be highly dependent on the tether length. A new phosphoramide based on a 2,2′-bispyrrolidine skeleton has been designed and afforded good yield, efficient turnover, and high enantioselectivity in allylation reactions. The synthesis of enantiopure 2,2′-bispyrrolidine was easily accomplished on large scale by photodimerization of pyrrolidine followed by resolution with L(or D)-tartaric acid. The scope of the allylation reaction was examined with variously substituted allylic trichlorosilanes and unsaturated aldehydes. This method has been applied to the construction of stereogenic, quaternary centers by the addition of unsymmetrically γ-disubstituted allylic trichlorosilanes.
