Cis nitro configuration

Then we designed and synthesized a series of neonicotinoids containing cis nitro configuration with the help of virtual screening and the aforementioned bioinformatic analysis as well as quantum chemical calculation. 

Cyclization of glutaraldehyde (129) with nitromethane, which, when first attempted, seemed unprofitable,121 has been so elaborated122,123 as to provide, in 66% yield, frans,frans-2-nitro-l,3-cyclo-hexanediol (130, R = H), the thermodynamically most stable of the three possible isomers (one dl and two meso forms). The reaction has been extended to include nitroethane,124,125 nitroethanol,128 ethyl nitroacetate125 [which gave, preponderantly, 130 (R = Me, CH2OH, and C02Et)], 1-nitropropane,124 and phenylnitromethane (a-nitro-toluene)124 [which yielded products 131 (R = Et and Ph) that had the Dlu-cis-trans configuration]. 

The cycloaddition reaction is stereospecific with respect to substituent configuration in both the dienophiie and the diene. The relative configurations of both the reactants are preserved in the product (the adduct). In the following reaction of 1,3-butadiene with cis-dinitroethene and frans-dinitroethene, the cis and trans relationships of the nitro groups in the dienophiles are preserved in the six-membered ring of the adducts, 8.9 and 8.10, respectively. 

Fundamental questions related to the electronic configuration of the open or colored forms and the number and structures of the photomerocyanine isomers are considered on the basis of the results of continuous-wave (stationary) and time-resolved (picosecond, nanosecond, and millisecond) Raman experiments. For spironaphthoxazine photochromic compounds, the Raman spectra may be attributed to the TTC (trans-trans-cis) isomer having a dominant quinoidal electronic configuration. Surface-enhanced resonance Raman spectroscopy (SERRS) is demonstrated as a new analytical method for the study of the photodegradation process in solution for nitro-BIPS derivatives. The development of this method could lead to the identification of the photoproducts in thin polymer films or sol-gel matrices and ultimately to control of degradation. 

Scheme 5 Isomers of cis- -MXjfS-Me-trien) . A-(-l-)-cis- -Co(NOj)2 5(/t)-Mc-trien has the (SS)-1 configuration while A-(+)-eis- -Co(NOj)2 5(/ )-Me-2,3,2-tct has the (SU)-II configuration. However, in both cases, the planar sec-NH proton is remote from the coordinated nitro group...

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