Steric C-N bond activation on the dimeric macrocycle [{P(μ-NR)}2(μ-NR)]2
Yan X Shi1, Rong Z Liang1, Katherine A Martin1
1School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore. fgarcia@ntu.edu.sg.
Abstract:
Dimeric cyclophosphazanes [{P(μ-NR)}2(μ-NR)]2 [R = (t)Bu ( 1) and iPr ( 3)] were oxidized with elemental selenium. During these reactions an unexpected C–N bond cleavage and N–H bond formation occurred. Compound 1 produced P4(μ-N(t)Bu)3(μ-NH)3Se4 ( 2) where three tBu groups were lost in the form of isobutylene. In contrast, during the oxidation of the less sterically hindered 3, the resulting product, P4(μ-N(i)Pr)5(μ-NH)Se4 ( 4), showed only one substituent loss. Theoretical studies confirmed the steric nature of the driving force underlying the different outcomes.
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