199 004, U.S.S.R.Complete optimization of single molecules of unsubstituted cyclic oxides (CO) differing in ring size and their complexes with electron acceptors (EA) by the CNDO/2 method allowed to establish some features of the electronic structure of these molecules non-monotonically depending on ring size with the extream for four-membered oxide. Calculated energies of complexation are in good agreement with experimental data on the reactivity of CO in cationic copolymerization. This confirms the dependence of the reactivity on basicity.
Anderung der Elektronenstrzdrtur yclischer Oxide bei der Wechselwirkung rnit Elektronenacceptoren. Quantenchemische UntersuchungenDie vollstandige Optimierung von Einzelmolekulen unsubstituierter cyclischer Oxide rnit unterschiedlicher RinggroSe sowie ihrer Komplexe mit Elektronenacceptoren mit Hilfe der CND0/2-Methode zeigte, da5 einige Charakteristika der Elektronenstruktur dieser Molekule nicht monoton von der RinggroDe abhangen, sondern bei den viergliedrigen Oxiden Extremwerte aufweisen. Die berechneten Komplexbildungsenergien stimmen rnit experimentellen Werten der Reaktivitat der Oxide bei der kationischen Copolymerisation gut iiberein. Dies bestatigt die Abhangigkeit der Reaktivitat von der Basizitat.
Hawnenue anemmponnoii cmpyxmypw yumuuecmux omuceii npu ux eaauntoaeiicmeuu c anexmpono-amq.enmopcueu. Keanmoxwuwcxue uccfieaoeanuanOJIHaH OIITHME3aL(Z ¶H El3OJIHpOBaHHbl.X MOJIeKyJI He3aMeWHHbnr IVfKJIHW?CKHX OKHCeB, paBJIM%3IO~HXCH IIO BeJIH9HHe qUKJIa, a TaKXG? HX KOMIIJIeKCOB C aJIeKTpOHOaK~eIITOpaMH MeTOAOM nnan/2 IIpHBeJIa K YCTaHOBJIeHHIO HeKOTOPbIX XapaKTepHCTHK aJIeKTpOHHOt CTpyKTypbI qUKJlUWCKHX OKECe8, He MOHOTOHHO 3aBHCHIIlHX OT pa3Mepa qHKJIa C aKCTpeMyMaMH AJIH 4-9JIeHHOfi OKHCH. PaCC ¶HTaHHbIe aHeprHH KOMIIJIeKCOO6paaOBaHHH XOpOJllO COI'JIaCJWTCH C aKCIIepHMeHTaJIbHbIMH AaHHbIMH IIO peaK~HOH~O~IIOCO6HOCTU IJHKJIH' ieCKHX OKHCefi IIpH KaTHOHHOfi UOJIHMepH3aqHH, YTO IIOATBepXAaeT 3aBHCHMOCTb peaKqZiOHHOCIIOCO6HOCTU OKHCeg OT HX OCHOBHOCTH.
Poly(2‐hydro‐2‐oxo‐1,3,2‐dioxaphosphorinane) was quantitatively chlorinated, and the resulting polymer was reacted with excess of imidazole, giving the highly reactive polyesteramide. This polymer, treated with N1‐hydroxyethyluracil, gave polyphosphates with N1‐oxoethyleneuracil in the side chains. The final polymers (M̄n ≈ 104) as well as the intermediate products were characterized by 1H‐, 13C‐ and 31P‐NMR spectroscopy.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.