cis-Azoxyalkanes. V. Concerted retrocycloaddition of nitrous oxide

Abstract

with those in the spectrum of the equimolar mixture (see footnote a to Table I for assignments) then points clearly to the contributions from CrmCl6 and Mo'^Cle chromophores in the spectrum of CrMoClg3-. This information makes it equally clear that reaction 3 involves electron transfer. Furthermore, the electronic spectrum of CrMoClg3is in full accord with a confacial, bioctahedral structure since this structure is the only one which will simultaneously accommodate both CrulCl6 and MoulCl6 chromophores. Finally, the magnetic moment per formula unit of [(«-C4H9)4N]3CrMoClg is 4.38 BM at 295°K and 3.10 BM at 77°K. These results are in accord with antiferromagnetic coupling between the two S = % spin systems.The only other dinuclear or polynuclear species containing both chromium and molybdenum is the Cr(II)-Mo(II)acetate compound, CrMo(OAc)4, which was recently prepared.6Acknowledgment. Financial aid from the National Science Foundation (Grant No. GP-30544X) is acknowledged. References and Notes(1) W.

cis-Azoxyalkanes. 8. Concerted thermal cycloreversion of unsaturated azo N-oxides

“…The second series is [13][14][15][16]. Enlargement of the saturated bridge causes a drastic reduction in rate.…”

“…Seen from an overall geometric viewpoint the symmetrical cycloreversion of azo 38 is unexceptional and in complete accord with a concerted process insensitive to reaction medium. 46 The A-oxide 13 decomposition is predicted to proceed in a single step but with unequal rates of cleavage of the C-N bonds. This is reflected by the variation of angle a (Figure 6) from -0.2°to a maximum of 13°, then back to zero as the fragments pass to infinite separation.…”

“…12 Recently we reported the parallel thermal extrusion of N20 from a series of unsaturated polycycles analogous to 2. 13 The relative rate differences for N2 vs. N20 loss are enormous although both processes appear to fulfill the pericyclic requirements. In the current study we present additional kinetic data and the results of SCF-MO potential energy surface calculations for the N2 and N20 extrusions.…”

“…Several attempts were made to prepare the bicycloheptadiene A-oxide 13 and the anthracene derivative 23. In the former case oxidative hydrolysis in various mixtures of water and ethylene glycol led only to the formation of cyclopentadiene. At 20 °C the starting adduct 4 ( = 1) disappeared slowly, whereas at 30-40 °C it reacted completely within half an hour.…”

Photoelectron spectra of cyclic azo N-oxides and azo N,N'-dioxides

“…azacyclohexene N-oxide (5), and 3,3,6,6-tetramethyl-l,2-diazacyclohexene N, '-dioxide (6) are presented in Figure 2. The corresponding vertical ionization potentials of compounds 1-6 are given in Table I.…”