Chapter 1
Nitrile Imines and Their Properties
Abstract This chapter introduces the nitrile imine 1,3-dipole, examining the history
behind its discovery and the core spectroscopic characteristics associated with the
species. The different resonance forms available to nitrile imines can often complicate
their characterisation, however appropriate interrogation of data such as UV-Vis,
IR and NMR spectra may elucidate the core properties of the dipole. Substitution
on either terminus of this typically highly reactive intermediate can also improve
stability, enabling the isolation of some nitrile imines at room temperature.
Keywords Nitrile imine · 1,3-dipole · Spectroscopy · Properties · Isolation
1.1 History
The generation of nitrile imines (NIs) can be traced back to the beginning of the
twentieth century, although these reports lacked both characterisation and application
of the highly reactive species. The first synthetically tractable report came from
Huisgen in 1959 [1]. This initial study was remarkably comprehensive, documenting
multiple approaches towards the generation of the NI and detailing its reactivity with
a number of dipolarophiles and nucleophiles. Huisgen dominated the area for much
of the next decade and provided invaluable insights into the reactivity, kinetics and
chemoselectivity of NIs through a number of publications [1–18].
Interest in the applications of NIs was more sparse over the next few decades, with
the majority of publications focussing instead on the mechanism of their formation,
or their reactivity with different substrates. Recently, however, NI chemistry has
enjoyed a renaissance throughout the literature, with a raft of applications identified
in the synthesis of APIs, bioorthogonal conjugation, and materials chemistry, over
the past fifteen years [19–21].
© Springer Nature Switzerland AG 2020
C. Jamieson and K. Livingstone, The Nitrile Imine 1,3-Dipole,
https://doi.org/10.1007/978-3-030-43481-6_1
1
Nitrile Imines and Their Properties
Abstract This chapter introduces the nitrile imine 1,3-dipole, examining the history
behind its discovery and the core spectroscopic characteristics associated with the
species. The different resonance forms available to nitrile imines can often complicate
their characterisation, however appropriate interrogation of data such as UV-Vis,
IR and NMR spectra may elucidate the core properties of the dipole. Substitution
on either terminus of this typically highly reactive intermediate can also improve
stability, enabling the isolation of some nitrile imines at room temperature.
Keywords Nitrile imine · 1,3-dipole · Spectroscopy · Properties · Isolation
1.1 History
The generation of nitrile imines (NIs) can be traced back to the beginning of the
twentieth century, although these reports lacked both characterisation and application
of the highly reactive species. The first synthetically tractable report came from
Huisgen in 1959 [1]. This initial study was remarkably comprehensive, documenting
multiple approaches towards the generation of the NI and detailing its reactivity with
a number of dipolarophiles and nucleophiles. Huisgen dominated the area for much
of the next decade and provided invaluable insights into the reactivity, kinetics and
chemoselectivity of NIs through a number of publications [1–18].
Interest in the applications of NIs was more sparse over the next few decades, with
the majority of publications focussing instead on the mechanism of their formation,
or their reactivity with different substrates. Recently, however, NI chemistry has
enjoyed a renaissance throughout the literature, with a raft of applications identified
in the synthesis of APIs, bioorthogonal conjugation, and materials chemistry, over
the past fifteen years [19–21].
© Springer Nature Switzerland AG 2020
C. Jamieson and K. Livingstone, The Nitrile Imine 1,3-Dipole,
https://doi.org/10.1007/978-3-030-43481-6_1
1