Structure of imidazoles

Chemical evidence for the structure of imidazol-4-ones has been summarized,although rather different conclusions would now be drawm from this evidence. For example, in the light of present knowledge, the ease with which imidazol-4-ones react with diazonium salts suggests that an appreciable amount of the 4-hydroxyimidazole exists... 

Figure 8.9 The chemical structure of imidazole and imidazoline, together with some well-known derivatives...

Electronic structure of imidazol-2-ylidene in the lowest singlet and triplet states proton affinity... 

Figure 7.48 Structures of imidazole-derived metallomacrocycles and crystal structure of the water/ methanol inclusion complex of 7.67.61...

Examination of the crystal structure of imidazole,179 involving measurement of the bond lengths, shows considerable double-bond... 

Imidazoles have also been prepared by three- and four-component reactions in a one-pot procedure [72], The structures of imidazoles obtained after cleavage from the resin with TFA/CH2CI2 are depicted in Fig. 1. 

X-ray studies have also revealed the ionic natures of imidazole quaternary salts <91ZN(B)1706>, the existence of clear parallels between the solid state and solution structures of imidazole and benzimidazole <83H(20)1713>, and the complete encapsulation of imidazolium perchlorate in benzo-3Q-crown-10. In the 1 1 complex the imidazole salt is coordinated to the host molecule by hydrogen bonding <89JOC1000>. 

Structure of imidazole resonance contributors (mesomeric structures)... 

Figure 3. Structures of imidazole and triazole antifungal compounds under investigation or in clinical use.

Ch. 1 General Properties and Structure of Imidazoles Ch. 2 The Alkyl- and Arylimidazoles... 

FIGURE 9.21. Structures of imidazole-modified poly(y-ethyl L-glutamate) and deuteroporphyrin-IX-Fe tl used by Grimshaw and Trocha-Grimshaw to construct an analog of cytochrome c (see Ref. 143). 

Holmes, R.R., Day, R.O., Yoshida, Y. and Holmes, J.M., Hydrogen-bonded phosphate-esters - synthesis and structure of imidazole-containing salts of diphenyl phosphate and (trichloromethyl)phosphonic acid, J. Am. Chem. Soc. 114 (5), 1771-1778 (1992). 

Figure S.14 Structure of imidazole (bond lengths in pm, bond angles in degrees).

Figure 1.39 Structure of imidazole showing that one lone pair is part of the aromatic jT-system, while the other is not.

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