Imidazole 2-pentyl

Several approaches to the 1,2,3-triazole core have been published in 2000. Iodobenzene diacetate-mediated oxidation of hydrazones 152 led to fused 1,2,3-triazoloheterocycles 153 <00SC417>. Treatment of oxazolone 154 with iso-pentyl nitrite in the presence of acetic acid gave 1,2,3-triazole 155, a precursor to 3-(W-l,2,3-triazolyl)-substituted a,P-unsaturated a amino acid derivatives <00SC2863>. Aroyl-substituted ketene aminals 156 reacted with aryl azides to provide polysubstituted 1,23-triazoles 157 <00HC387>. 2-Aryl-2T/,4/f-imidazo[43-d][l,2,3]triazoles 159 were prepared from the reaction of triethyl AM-ethyl-2-methyl-4-nitro-l//-imidazol-5-yl phosphoramidate (158) with aryl isocyanates <00TL9889>. 

N-(4-Dimethylamino-phenyl)- E16a, 96 [- N(OH) - N = NH-Spalt.] N-Methyl-N-[2-(2-pyridyl)-ethy]]-E16a, 128 (R-NH-OH + En) N-Methyl-N-[2-(4-pyridy )-ethyl]-E16a, 129 (R-NH-OH + En) Imidazol 4(5)-(l-Hydroxy-cyclo-pentyl)- E8c, 157 (Br-imidazol/... 

Imidazol 4-Aminocarbonyl-5-(3-methyl-3-pentyl-1 -triazeno)-E16a, 1199 (Het-Nf + Amin)... 

To date, there has been no report of the nitrosation of imidazole itself. There are, however, a number of examples of nitrosation of substituted imidazoles in basic medium. The observation that such reactions do not occur with Af-substituted imidazoles implicates the imidazole anion as the likely substrate. Substitution generally occurs at C-4 or C-5 and may be accompanied by some nitration. In the presence of sodium ethoxide, pentyl nitrite nitrosates 4-phenyl-, 2-methyl-5-phenyl- and 2,5-diphenyl-imidazoles at the vacant 4- or 5-positions. The reaction apparently failed with 5-methyl-2-phenyl- and 4,5-diphenyl-imidazoles (58G463). 

Basificaiion with aqueous alkali and re-extraction with ether, drying, and removal of the solvent gives the imidazole. Recrystallization may be necessary. Prepared in this way have been 2-pentyl- (75%), 2-phenyl- (85%), 1-methyl-2-pentyl- (33%) and 1-methy 1-2-phenyl- (42%) imidazoles. 

An aq. soln. of 6-amino-7-octanone-l-carboxylic acid hydrochloride mixed with NH4-thiocyanate, evaporated to dryness on a steam bath during K hrs., the product evaporated twice with water, HC1 added, and allowed to stand 24 hrs. —l-methyl-5- (fo-carboxy-n-pentyl)-imidazole-2-thione. Y 69%. (F. e. with lower yields s. G. Swain, Soc. 1948, 1552.)... 

Dihydro-5-pentyl-2(3h)-furanone 9,10-Dihydrophenanthrene 2,3-Dihydro-2-phenyl-4W-1-benzopyran-4-one 4,5-Dihydro-2-(phenylmethyl)-1//-imidazole, monohydrochloride... 

Formation of one-dimensional channels with no rotation was observed in the complexes between per-ethylated pillar[5]arene 6.3 and l,4-his(imidazol-l-yl)butane (Figure 6.13d). The assembly of host-guest complexes of 5-bromovaleronitrile and a non-symmetrical pillar[5]arene with five methyls on one side and five n-pentyls on the other (6.22) also formed onedimensional channels (Figure 6.13e). The application incorporating the alignment of these guest molecules in the one-dimensional channels constructed from pillar[5]arenes is a topic for future investigation. 

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