Hydrogen isocyanide

Loss of Hydrogen Isocyanide from Aromatic Amines... 

The mass spectrum of aniline has been known since the early days of mass spectrometry. [122] Initially, the observed [M-27] ion has been interpreted in terms of HCN loss (Fig. 6.56a). The mechanism for loss of the elements of [H, N, C] from aminoarenes is perfectly analogous to CO loss from phenols (Chap. 6.9.1). [231] More recently, it could be demonstrated that loss of hydrogen isocyanide, HNC, occurs rather than losing the more stable neutral species HCN, a behavior typical of ionized pyridine. [222]... 

Burgers, P.C. Holmes, J.E. Mommers, A.A. Terlouw, J.K. Neutral Products of Ion Fragmentations Hydrogen Cyanide and Hydrogen Isocyanide (HNC) Identified by Collisionally Induced Dissociative Ionization. Chem. Phys. Lett. 1983,102,1-3. 

The BE-matrices of hydrogen cyanide and hydrogen isocyanide (notice that since the neutral "carbenic" resonance structure has not the octets fully completed, the dipolar resonance structure is taken instead) are ... 

Let us consider the rearrangement of hydrogen cyanide to hydrogen isocyanide ... 

Cyclohexen-l-yl isocyanide 1 known as Armstrong convertible isocyanide has also been called universal isocyanide . It was prepared in 1963 by Ugi and Rose-ndahl [5] to be used as a synthetic equivalent of the unknown hydrogen isocyanide . The Ugi-4CR between 1, cyclohexanone N-benzylimine 2, and formic acid afforded N-cyclohexen-l-yl amide 3, which was cleaved in acidic medium to afford the primary a-acylamino amide 4 rather than the N-substituted amides usually obtained by the Ugi-4CR (Scheme 2.1). 

Scheme 2.1. 1-Cyclohexen-1-yl isocyanide as a synthetic equivalent of hydrogen isocyanide.

In a study of the reaction of alkynes with hydrogen isocyanide the condensed Fukui function was combined with the overall or global softness to try to rationalize the regioselectivity of attack on the triple bond [153] ... 

As the simplest example of the MD simulation along the IRC, the isomerization of hydrogen cyanide to hydrogen isocyanide has been chosen, This reaction has been extensively studied by both experimental and theoretical methods53-59 and widely used as a test case for the IRP determination methods.60-65... 

Figure 4-10. Isomerisation of hydrogen cyanide to hydrogen isocyanide the IRC energy profile (panel a), and the free-energy profile together with the average potential energy profiles (panel b), calculated from the 300K MD simulations along the IRP...

Pan CF, Hehre WJ, Heat of formation of hydrogen isocyanide by ion cyclotron double resonance spectroscopy, J Phys Chem, 86, 321 (1982)... 

This section presents a discussion of the treatment outlined above applied to a realistic molecular reaction. For simplicity we have chosen the isomerization of hydrogen cyanide (HCN) to form hydrogen isocyanide (HNC) because it is commonly used as model system in the study of isomerization reactions. This reaction, which has been the subject of innumerable studies, is excellent for our purposes. While the system is small (only three atoms) it does possess sufficient complexity to be an excellent test case. The importance of this system as a test case, both experimentally and theoretically, is demonstrated by the size of the literature [82,83-141]. This list is by no means exhaustive, nor particularly representative. 

Hydrogen isocyanide complexes 46, generated in situ, have been reacted with carbodiimides to give isocyanocarboxamidines 47. ... 

Oxazolin-2-ylidenes can also be used directly for coordination to metal atoms [109], but then they are not functionalised and therefore not covered by this book. However, it may be interesting to note that their generation is possible as a template synthesis in the coordination sphere of transition metal complexes using a functionalised hydroxyisocyanide [110,111] or the reaction of an epoxide with a hydrogen isocyanide complex [112]. 

Theoretical description of the hydrogen cyanide-hydrogen isocyanide and lithium cyanide-lithium isocyanide isomerization using the FSGO method. ... 

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