10.1021/ja031538i.s001
Joseph E. Saavedra
Joseph E.
Saavedra
D. Scott Bohle
D. Scott
Bohle
Kamilah N. Smith
Kamilah N.
Smith
Clifford George
Clifford
George
Jeffrey R. Deschamps
Jeffrey R.
Deschamps
Damon Parrish
Damon
Parrish
Joseph Ivanic
Joseph
Ivanic
Yan-Ni Wang
Yan-Ni
Wang
Michael L. Citro
Michael L.
Citro
Larry K. Keefer
Larry K.
Keefer
Chemistry of the Diazeniumdiolates. O- versus N-Alkylation of
the RNH[N(O)NO]<sup>-</sup> Ion
American Chemical Society
2004
p K
isopropyl
Ion Monomethylation
theory calculations
terminal oxygen
1 H NMR spectrum
ionization
bathochromic shift
NH bond
RNH
NN
RNHN
B 3LYP basis sets
bond order
novel diazeniumdiolate
access synthetically
Gaussian 03
max
nitric oxide
2004-10-13 00:00:00
Dataset
https://acs.figshare.com/articles/dataset/Chemistry_of_the_Diazeniumdiolates_O_versus_N_Alkylation_of_the_RNH_N_O_NO_sup_sup_Ion/3321010
Monomethylation of the potentially ambident RNH[N(O)NO]<sup>-</sup> ion (R = isopropyl or cyclohexyl)
has been shown to occur at the terminal oxygen to yield the novel diazeniumdiolate structural unit, RNHN(O)NOMe. The NH bond of the product proved acidic, with a p<i>K</i><sub>a</sub> of 12.3 in aqueous solution. The ultraviolet
spectrum showed a large bathochromic shift on ionization (λ<sub>max</sub> 244 → 284 nm, ε<sub>max</sub> 6.9 → 9.8 mM<sup>-1</sup> cm<sup>-1</sup>).
Deprotonation led to a pH-dependent line broadening in the <sup>1</sup>H NMR spectrum of <i>i</i>PrNHN(O)NOMe,
suggesting a complex fluxionality possibly involving isomerizations around the N−N bonds. Consistent
with this interpretation, evidence for extensive delocalization and associated changes in bond order on
ionizing RNHN(O)NOR‘ were found in density functional theory calculations using Gaussian 03 with B3LYP/6-311++G** basis sets. With MeNHN(O)NOMe as a model, all NN and NO bonds lengthened by
0.04−0.07 Å as a result of ionization except for the MeN−N linkage, which shortened by 7%. These anions
can be N-alkylated to generate R<sup>1</sup>R<sup>2</sup>NN(O)NOR<sup>3</sup> derivatives that would otherwise be difficult to access
synthetically. Additionally, some RNHN(O)NOR‘ species may display unique and beneficial pharmacological properties. As one example, an agent with R = isopropyl and R‘ = β-d-glucosyl was prepared and
shown to generate nitric oxide in the presence of glucosidase at pH 5.