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US 3,941,802 AGranted
2-(Imidazol-1-yl)benzophenones
AssigneeThe Upjohn Company
InventorMartin Gall
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AssigneeThe Upjohn Company
InventorMartin Gall
Estimating the term…
Compounds of the formulae IV and V: ##SPC1## wherein R.sub.o and R.sub.1 are hydrogen or alkyl of 1 to 3 carbon atoms, inclusive; wherein R.sub.2 is hydrogen, fluoro, chloro, or trifluoromethyl; wherein R.sub.3 is hydrogen or fluoro with the proviso that R.sub.3 cannot be fluoro, if R.sub.2 is chloro or trifluoromethyl; and wherein R.sub.4 is hydrogen, fluoro, chloro, bromo, trifluoromethyl, or nitro, are obtained by a multi-step reaction from the corresponding .alpha.-(phenyl)-o-toluidine of the formula I ##SPC2## wherein R.sub.2, R.sub.3, and R.sub.4 are defined as above, by treating I in sequence with an alkyl ester of orthoformic acid the resulting product with 2-alkyl-2-(aminoalkyl)-1,3-dioxolane or a 2-amino-alkanone dialkyl ketal and finally with titanium tetrachloride to obtain compound IV, and oxidizing compound IV to obtain the corresponding compound V. Compounds IV and V have minor tranquilizing activity which can be utilized to calm mammals or birds. Their more important use, however, is as intermediates in the production of the strongly sedating and tranquilizing imidazolobenzodiazepines.
A compound of the formula V:
Dependencies are inferred from the claim text.
No related US applications are recorded in the indexed filing history.
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Having two double bonds between ring members or between ring members and non-ring members: with only hydrogen atoms or radicals containing only…
Compounds containing nitrogen atoms doubly-bound to a carbon skeleton: hydrazones
Having two or three double bonds between ring members or between ring members and non-ring members: with only hydrogen atoms, hydrocarbon or…
Not condensed with other rings: 1,2,4-Triazoles; Hydrogenated 1,2,4-triazoles
Term ended 2 Mar 1993 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
1. Field of the Invention
This invention is directed to new organic compounds and more specifically to 1-(.alpha.-phenyl-0-tolyl)imidazoles and 2-(imidazol-1-yl)benzophenones and a process of the production therefor.
The new compounds and the process therefor is illustratively represented as follows: ##SPC3##
The following preparations and examples are illustrative of the processes and products of the present invention, but are not to be construed as limiting.
A mixture of 27.2 g. (0.117 mol) of 2-amino-5-chlorobenzophenone in 170 ml. of diethylene glycol and 23 ml. (0.45 mol) of 99% hydrazine hydrate is brought to reflux for a total of 7 hours. The solution is allowed to cool overnight to room temperature. The light green-colored solid which results is mixed with 400 ml. of water and extracted into benzene; the layers are separated and the benzene portion dried over anhydrous magnesium sulfate and concentrated. Crystallization of the residue from ether/hexane gives 13.5 g. (46.8%) 2-amino-5-chlorobenzophenone hydrazone of melting point 133.degree.-133.5.degree. C.
Anal. calcd. for C.sub.13 H.sub.12 ClN.sub.3 : C, 63.55; H, 4.93; N, 17.11; Cl, 14.43. Found: C, 63.58; H, 4.95; N, 17.32; Cl, 14.39.