A novel asymmetric synthesis of highly enantiomerically enriched norbornane-type diamine derivatives

Özçubukçu, Salih
The simple and highly enantioselective methanolysis of norbornene dicarboxylic acid anhydride mediated by quinidine leads to the corresponding cis-monomethyl ester with 98% ee. By means of selective ester epimerization, followed by Curtius degradation of the intermediate trans-diacyl azide, two optically active norbornane-type diamines are obtained as their hydrochloric salts. Liberating the amine with an excess of triethylamine in situ and subsequent derivatization affords potential C-1-symmetric ligands for asymmetric catalysis in excellent yields.


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Demir, Ayhan Sıtkı; Caliskan, Z; Aydin, AE; Bicer, I (Elsevier BV, 2006-03-06)
A chemoenzymatic synthesis of both enantiomers of the pharmacologically interesting alpha'-acetoxy and alpha'-hydroxy-alpha-methoxy cyclic enones starting from alpha-hydroxy cyclic enones is described. Protection of 1,2-diketones, manganese(III) acetate-mediated acetoxylation followed by enzyme-mediated hydrolysis of alpha'-acetoxy enones gives acetoxy enones 3a-d and hydroxy enones 4a-d with high enantiomeric excesses (up to 99%) and good yields. The transesterification of rac-4b in the presence of DMAP af...
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A new and efficient chemoenzymatic route to both enantiomers of alpha '-acetoxy-alpha-methyl and gamma-hydroxy-alpha-methyl cyclic enones
Demir, Ayhan Sıtkı; Findik, H; Kose, E (Elsevier BV, 2004-03-08)
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One-step synthesis of hierarchical [B]-ZSM-5 using cetyltrimethylammonium bromide as mesoporogen
Yalcin, Busra Karakaya; İpek Torun, Bahar (The Scientific and Technological Research Council of Turkey, 2020-01-01)
One-step facile synthesis of boron containing ZSM-5 microspheres is developed using 1,6-diaminohexane as the structure-directing agent and cetyltrimethylammonium bromide as the mesoporogen. High boron incorporation up to Si/B ratio of 38 is achieved and evidenced by the stretching vibrations of B-O-Si at 667 cm(-1) and 917 cm(-1) using Fourier-transform infrared spectra. The morphology of the crystals resembles berry-like spheres with sizes approximately 15 mu m, which is composed of aggregated nanocrystals...
Citation Formats
C. BOLM, I. SCHİFFERS, I. ATODİRESEİ, S. Özçubukçu, and G. RAABE, “A novel asymmetric synthesis of highly enantiomerically enriched norbornane-type diamine derivatives,” NEW JOURNAL OF CHEMISTRY, pp. 14–17, 2003, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/37722.