Benzyl imidazolates

The benzyloxycarbonyl protecting group for amines is introduced in high yield using benzyl imidazole-carboxylate with a catalytic amount (5%) of dimethylamino-pyridine.[1953... 

Burke, B.J. and Hopfinger, A.J. l-(Substituted-benzyl)imidazole-2(3H)thione inhibitors of dopamine... 

Durch katalytische Hydrierung mit Raney-Nickel in Ethanol bei 100 bar/100o lassen sich 1,2-disubstituierte 4- oder 5-Chlor-imidazole497 zu 1,2-disubstituierten Imidazolen und mit Palladium auf Aktivkohle in Eisessig 4-Acetylamino-l-benzyl-2-brom-imidazol498 zu 4-Acetyl-amino- 1-benzyl-imidazol enthalogenieren. 

Die Umsetzung von l-Benzyl-imidazol-3-oxiden mit Phosphor(III)-chlorid fiihrt unter Bildung von Phosphoroxychlorid in guten Ausbeuten zu den entsprechenden 1-Benzyl-imidazo-len511. 

Das primar gebildete 4(5)-(methoxy-benzyl)-imidazol wird unter den Reaktionsbedingungen zum Keton nxidiert... 

SchlieBlich sei die Metallierung von 1-Benzyl-imidazol und am Phenyl-Ring substituierten 1-Arylmethyl-imidazolen genannt (vgl. a.S. 110). Durch Umsetzung mit Butyl-lithium und Ben-zyl-halogeniden laBt sich hier selektiv eine Benzyl-Gruppe am Methylen-Rest der Seitenkette einfuhren1148. 

Lateral metalation can be a complication, and this occurs in compounds such as 1,2-dimethyl- and 1-benzyl-imidazoles, and with 2-methyl- and 2-benzyl-benzimidazoles. Subsequent reactions of these compounds take place at the side-chain carbanion centre (73JOC4379, 74JOC2301). 

Janssen, P. A. J., Niemegeers, C. J. E., Schellekens, K. H. I., Lenaerts, F. M. Etomidate, R-(+)-ethyl-l-(a-methyl-benzyl)imidazole-5-carboxylate (R 16659), a potent, short-acting and relatively atoxic intravenous hypnotic agent in rats. Arzneim.-Forsch. 21, 1234 (1971). 

Starting with the benzyl-imidazole (compound 1), which binds to angiotensin II (All) receptor but exhibits a very poor potency, Duncia et supposed that a second acidic group (compound 2) would provide, at physiological... 

Zur reduktiven Spaltung von 2-Methyl-1-benzyl-imidazol mit Natrium/fl. Ammoniak zu 2-Methyl-imidazol s.ds. Handb. Bd. XI/1, S. 974. 7-Chlor-4-amino-(bzw. 4-alkylami-no)-l-benzyl-l//-(imidazo-[4,5-d]-pyridazine) werden auf analoge Weise sowohl an der 1- wie an der 7-Stellung reduziert2 ... 

Butyl-4-chloro-1-[p-(o-1H-tetrazol-5-ylphenyl)benzyl]-imidazole-5-... 

The partially O-benzylated imidazol-4-yl acyclo C-nucleoside 403 (Section VIII,D,2 Scheme 111) wascyclized with tetramethylazodicarboxamide to 404 (95TL3165) (Scheme 97). 

There have been examples using Pd to couple aryl iodides directly to the 5 position of the imidazole ring. In the example shown, JV-benzyl imidazole coupled with phenyl- or methoxy-phenyliodides efficiently and was subsequently brominated at the 4-position to undergo further reaction. ... 

In parallel with the directed hydroarylation of olefins, a series of papers described the formation of ketones from heteroarenes, carbon monoxide, and an alkene. Moore first reported the reaction of CO and ethylene with pyridine at the position a to nitrogen to form a ketone (Equation 18.28). Related reactions at the less-hindered C-H bond in the 4-position of an A/-benzyl imidazole were also reported (Equation 18.29). - Reaction of CO and ethylene to form a ketone at the ortho C-H bond of a 2-arylpyridine or an N-Bu aromatic aldimine has also been reported (Equations 18.30 and 18.31). Reaction at an sp C-H bond of an N-2-pyridylpiperazine results in both alkylative carbonylation and dehydrogenation of the piperazine to form an a,p-unsaturated ketone (Equation 18.32). The proposed mechanism of the alkylative carbonylation reaction is shown in Scheme 18.6. This process is believed to occur by oxidative addition of the C-H bond, insertion of CO into the metal-heteroaryl linkage, insertion of olefin into the metal-acyl bond, and reductive elimination to form the new C-H bond in the product. 

C38Hft2Co2N608, N,N -Ethylenebis(salicylideneiminato)cobalt(II) -oxygen - dimethylformamide adduct, 35B, 781 C3 eH sCoNijOi, 1.5 C HgO, Dioxygen-N,N - (1, 1,2,2 tetramethyl)ethyl-enebis(3-t butylsalicylideniminato)(1-benzyl imidazole)cobalt(II) acetone solvate, 42B, 753... 

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