69533-68-2Relevant academic research and scientific papers
Microwave-assisted novel stereoselective synthesis of bis-β-lactams with 2,7-phenanthrenyl imines
Yadav, Ram Naresh,Banik, Indrani,Banik, Bimal Krishna
, p. 1377 - 1380 (2020/06/27)
Microwave-induced stereoselective synthesis of novel bis-β-lactams substituted at the 2,7 position of the phenanthrene has been performed via ketene-imine [2+2] cycloaddition reaction.
Optical spectra of protected diamine 10-bond-bridged intervalence radical cations related to N,N,N′,N′-tetraalkylbenzidine
Nelsen, Stephen F.,Luo, Yun,Weaver, Michael N.,Lockard, Jenny V.,Zink, Jeffrey I.
, p. 4286 - 4295 (2007/10/03)
The optical absorption spectra of the delocalized intervalence radical cations of seven o,o′-linked benzidine derivatives that have the nitrogens protected as 9-(9-aza-bicyclo[3.3.1]nonan-3-one) derivatives are discussed and compared with that of the p-phenylene radical cation. The linking units are CH2, CH2CH2, NMe, S, SO2, and C=O, and we also studied H,H (the unlinked benzidine). The lowest-energy absorption band is assigned as the transition from the antibonding combination of symmetrical N and aromatic orbitals to the antibonding combination of the antisymmetric N and aromatic orbitals using TD-DFT calculations, and a good correlation between the observed transition energies and those calculated using the simple Koopmans theorem-based "neutral in-cation geometry" calculations on the UB3LYP/6-31G* structures is found. The use of the two-state model that equates the electronic interaction through the bridge between the amino groups with half of the lowest transition energy is seriously incorrect for these and other delocalized intervalence compounds. The problem of extracting the electronic interactions that actually are involved from calculated transition energies is discussed.
Effects of additional linkers in biphenyl-4,4′-dinitrene on the low-lying singlet-triplet energy gap and zero-field splitting
Nimura,Kikuchi,Ohana,Yabe,Kondo,Kaise
, p. 2083 - 2088 (2007/10/03)
Perturbation effects of additional linkers on the spin-spin coupling in biphenyl-4,4′-dinitrene (1) were examined by introducing a linking group between 2- and 2′-positions of 1. Five different doubly linked systems showed triplet ESR spectra corresponding to quinonoid dinitrenes. Curie law analyses suggested that all those triplet states were thermally excited triplet states. In addition, the singlet-triplet energy gaps, which were determined by the Curie law analyses, were well correlated with their corresponding zero-field-splitting (zfs) D values. The result could be explained by the stability of dinitrene character which is estimated from the resonance energy of the intervening π-system. Our semiempirical molecular orbital calculations supported the experimental correlation between the singlet-triplet energy gap and the zfs D value.
Molecular structure of rac-(4R*,4aS*,10aS*)-4-nitro-1,2,3,4,4a,9,10,10a-octahydrophenanthren-4a-ol, an unusual by-product of nitration of a crude 9,10-dihydrophenanthrene
Fernandez, Franco,Lerma, J. Lopez De,Perales, Aurea,Rodriguez, Gonzalo
, p. 451 - 456 (2007/10/02)
A new nitro-octahydrophenanthrenol has been isolated by nitration of a crude 9,10-dihydrophenanthrene, which was identified by nmr and X-ray diffraction analysis.Crystallographic and molecular structure confirmed the compound as the rac-(4R*,4aS*,10aS*)-4-Nitro-1,2,3,4,4a,9,10,10a-octahydrophenanthren-4a-ol.The crystal was triclinic, P, a=10.549(3), b=8.530(3), c=7.131(1) Angstroem, α=107.07(3), β=91.62(3), γ=96.27(4)o.Cyclohexane and cyclohexene rings are trans-fused and have chair and half-chair conformations, respectively.The molecules are associated by hydrogen bridge between the hydroxyl oxygen and both nitro oxygens.KEY WORDS: C14H17NO3, chair, half-chair.
