Imidazolyl chloride

The reaction of 2-methyl-2-phenylpropanal and GaCl3 gave a rearranged phenyl isopropyl ketone, in which phenyl migration proceeded to the carbonyl carbon as induced by GaCls (Scheme 7.25) [47]. Imidazolyl chloride was used as the acid... 

Carbene complexes have also been prepared by transmetallation reactions. Lithiated azoles react with gold chloride compounds and after protonation or alkylation the corresponding dihydro-azol-ylidene compounds, e.g., (381) or (382), are obtained.22 9-2264 Silver salts of benz-imidazol have also been used to obtain carbene derivatives.2265 Mononuclear gold(I) carbene complexes also form when trimeric gold(I) imidazolyl reacts with ethyl chlorocarbonate or ethyl idodate.2266,2267 The treatment of gold halide complexes with 2-lithiated pyridine followed by protonation or alkylation also yields carbene complexes such as (383).2268 Some of these carbene complexes show luminescent properties.2269-2271... 

Ye et al. reported that the reduction of 2,4-dichlorophenyl-2-chloroethanone 1 with potassium borohydride in dimethylformamide to give 90% a-chloromethyl-2,4-dichlorobenzyl alcohol 2. Alkylation of imidazole with compound 2 in dimethyl formamide in the presence of sodium hydroxide and triethylbenzyl ammonium chloride, gave l-(2,4-dichlorophenyl-2-imidazolyl)ethanol 3 and etherification of 3 with 2,4-dichlorobenzyl chloride under the same condition, 62% yield of miconazole [9]. 

Butoconazole Bntoconazole, l-[4-(4-chlorophenyl)-2-[(2,6-dichlorophenyl)thio]butyl]-IH-imidazole (35.2.12), is synthesized from 4-chlorobenzylmagnesium bromide, which is reacted with epichloridrine to make 4-(4 -chlorophenyl)-l-chlorobutan-2-ol (35.2.10), which is reacted with imidazole in the presence of sodium to make 4-(4 -chlorophenyl)-l-(lH-imidazolyl)butanol-2 (35.2.11). The hydroxyl group in the last is replaced with a chlorine atom npon reaction with thionyl chloride, which is then by the reaction with 2,6-dichlorothiophenol bntoconazole [27,28], is obtained. 

Palladium-catalyzed cross-coupling reactions are not restricted to stannane derivatives, however, and other azaheterocyclic carbanion derivatives to have been investigated include l-methyl-2-pyrrolylmagnesium bromide and l-methyl-2-pyrrolylzinc chloride (81TL5319), l-methyl-2-indolymagnesium bromide (81TL5319), l-substituted-2- and 5-imidazolyl-... 

Cz Symmetrical and enantiomerically pure thiepines were prepared <1999TL813, 20060BC2218>. Diaryl compounds with two chiral centers 176 were lithiated with sec-butyl lithium in THF at — 78 °C to give the bis-ortho-lithiated 177. Reaction of sulfur diimidazole led to thiepines 26 and 178 in 37—48% yield (Scheme 20). The use of elemental sulfur, thionyl chloride, sulfuryl chloride, SC12, S02(imidazolyl)2, SO(imidazolyl)2, sulfur ditriazole, and sulfur bisbenzotriazole, as a sulfur electrophile, gave cyclized products in poor results. 

Several stereoselective syntheses of 4-(ribofuranosyl)imidazole nucleosides were reported. Imidazole 53 was obtained from 50 by a Mitsunobu cyclization [95TL3165]. Treatment of a suitably protected ribofuranosyl chloride with two equivalents of a lithioimidazole afforded the 1-(5-imidazolyl)ribofuranoid glycal (54) directly which undergoes elimination to the furylimidazole (55) [95CPB152]. 

In acetic acid solution 30% hydrogen peroxide converts 2-imidazolyl methyl sulfides into sulfones" " and sometimes sulfoxides. In tri-fluoracetic acid the sulfoxides are formed preferentially periodate, too, can give the sulfoxides. Oxidation of 4-mercaptoimidazoles under mild conditions gives bis(4-imidazolyl) disulfides which can be cleaved by hydrogen sulfide. With 15% alkaline hydrogen peroxide at 90°C the sulfonic acid is the major product. Imidazole-5-sulfonyl chlorides give sulfonamides... 

Hydroxyamino)benzodiazepine (90) is acylated on oxygen upon reaction with acid chlorides (acetyl or benzoyl chloride) or isocyanates (methyl isocyanate) in the cold. On heating with acetic anhydride at 100°C, there is an oxido-reductive rearrangement to give the 3-acetoxy-2-methylamino derivative (91) (Scheme 14). This is considered to proceed by isomerization of the nitronium ion formed by cleavage of the N—O bond to the 3-carbonium ion which is trapped by the nucleophile (acetate) <80AP(313)926>. A similar mechanism is used to explain the formation of the 3-(l-imidazolyl) derivative (92) on reaction of (90) with carbonyl diimidazole. 

Ferrocenyl(alkyl)imidazole. A new method for the introduction of imidazolyl groups into ferrocenylafkyl compounds by the ferrocenylafkylation reaction of 1 was reported. A mixture of equimolar amounts of ferrocenylcarbinols (27) and 1 in methylene chloride was boiled for 1 h, and A-ferrocenyl(alkyl)imidazoles (28) were synthesized in high yields (eq 24). 

The most appropriate technical synthesis of triazoxide [60], as described in Scheme 21.5, starts with phosgenation of 2-nitro-4-chloroaniline, followed by am-monolysis of the isocyanate. Cyclization of the formed arylurea occurs by treatment with aqueous sodium hydroxide to obtain the sodium salt of 3-hydroxy-7-chloro-l,2,4-benzotriazine-l-oxide. After acidification, the hydroxy group can be converted into the corresponding imidazolyl derivative after being transformed into the chloro compound with thionyl chloride. 

DL-l-Carboxy 2-(2-mercapto-4- HL/H.L imidazolyl)ethyl(trimethyl)-ammonium (chloride) ... 

Sulfur dichloride in dry methylene chloride added dropwise during 2-3 hrs. initially at ca. -95° and toward the end of the addition at ca. -80° to an acetone-liq. Ng-cooled mixture of n-butanol, triethylamine, and methylene chloride, then allowed to warm to 0° di-n-butyl sulfoxylate. Y 70%. Q. E. Thompson, J. Org. Ghem. 30, 2703 (1965) with di-(l-imidazolyl) sulfide s. L.Birkofer and H. Niedrig, B. 99, 2070 (1966). 

For the methacrylation of polysaccharides, several examples of dextran modification have been reported, for instance using maleic anhydride (5 methacryloyl chloride (6) or glycidyl methacrylate (7) as modifiers. Here we report the use of 2-[(l-imidazolyl) formyloxyjethyl methacrylate (HEMA-Im) as an efficient and more convenient agent for the methacrylation of polysaccharides (8). 

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