Claims
- 1. A process for removing a sulfonyl group of the formula RSO.sub.2 from the 1-position of a benzimidazole compound which consists essentially of
- reacting a benzimidazole compound of the formula O ##STR18## with an alkali metal hydroxide or carbonate in an inert aqueous organic solvent system selected from acetone, dimethoxy ethane, tetrahydro furan and tertiary amides at a temperature from about 20.degree. C. to about 100.degree. C., wherein
- R is C.sub.1 -C.sub.5 alkyl, C.sub.3 -C.sub.7 cycloalkyl, phenyl, furyl, or thienyl;
- R.sup.3 is C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, halo, nitro, C.sub.1 -C.sub.4 alkylthio, phenylthio, phenoxy, carboxy, methylsulfonyl, trifluoromethyl, ##STR19##
- R.sup.4 is hydrogen, C.sub.1 -C.sub.7 alkyl, C.sub.3 -C.sub.7 cycloalkyl, (C.sub.3 -C.sub.7 cycloalkyl)methyl, 1-(C.sub.3 -C.sub.7 cycloalkyl)ethyl, thienyl, benzyl, phenyl, or mono-substituted phenyl wherein said phenyl substituent is selected from the group consisting of C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, chloro, bromo. iodo, nitro, and trifluoromethyl;
- R.sup.6 is hydrogen, C.sub.1 -C.sub.7 alkyl, C.sub.3 -C.sub.7 cycloalkyl, (C.sub.3 -C.sub.7 cycloalkyl)methyl, 1-(C.sub.3 -C.sub.7 cycloalkyl)-ethyl, phenyl, or mono-substituted phenyl, wherein said phenyl substituent is selected from the group consisting of C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, chloro, bromo, iodo, nitro, and trifluoromethyl;
- R.sup.7 and R.sup.8 independently are hydrogen, halo, cyano, hydroxymethyl, nitro, ##STR20## CH.sub.2 R.sup.9, COR.sup.9, phenyl or mono-substituted phenyl, wherein said phenyl substituent is selected from the group consisting of C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, chloro, bromo, iodo, nitro, and trifluoromethyl;
- R.sup.9 is hydroxy, C.sub.1 -C.sub.4 alkoxy, halo, C.sub.3 -C.sub.6 cycloalkyl C.sub.1 -C.sub.4 alkoxy, or (O--C.sub.1 -C.sub.4 alkyl).sub.p NR.sup.10 R.sup.11 wherein
- R.sup.10 and R.sup.11 independently are hydrogen or C.sub.1 -C.sub.4 alkyl;
- Z is oxygen, C.sub.1 -C.sub.7 alkylidene, or C.sub.1 -C.sub.4 alkoxyimino;
- Y is hydrogen, and W is hydroxy, or together Y and W form a bond;
- m is 0, 1, or 2; and
- p is 0 or 1.
- 2. The process of claim 1 wherein the alkali metal hydroxide or carbonate is sodium hydroxide and the solvent in the aqueous organic solvent system is acetone.
- 3. The process of claim 1 wherein there is one equivalent of the alkali metal hydroxide or carbonate.
- 4. The process of claim 1 wherein
- R is isopropyl;
- R.sup.3 is ##STR21## R.sup.4 and R.sup.6 are phenyl or mono-substituted phenyl; and Z is oxygen or C.sub.1 -C.sub.7 alkylidene.
- 5. The process of claim 4 wherein
- R.sup.4 and R.sup.6 are phenyl;
- Y and W together form a bond; and
- Z is oxygen or ethylidene.
- 6. The process of claim 5 wherein R.sup.3 is ##STR22## and Z is oxygen.
- 7. The process of claim 6 wherein there is one equivalent of the alkali metal hydroxide or carbonate, which is sodium hydroxide, and the solvent in the aqueous organic solvent system is acetone.
- 8. The process of claim 5 wherein R.sup.3 is ##STR23## and Z is ethylidene.
- 9. The process of claim 8 wherein there is one equivalent of the alkali metal hydroxide or carbonate, which is sodium hydroxide, and the solvent in the aqueous organic solvent system is acetone.
CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation-in-part of application Ser. No. 366,759, filed Apr. 8, 1982 now abandoned.
US Referenced Citations (10)
Non-Patent Literature Citations (4)
Entry |
Sidgwick, The Organic Chemistry of Nitrogen, (1966) p. 251. |
Smith, The Chemistry of Open-Chain Organic Nitrogen Compounds, vol. I, (1965) pp. 188-189. |
Wright, Chem. Reviews, 48, 486-487 (1951). |
Price, et al. "Some Sulfonamide Derivatives of 2-Aminobenzimidazole." J. Org. Chem. 12, 269-274 (1947). |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
366759 |
Apr 1982 |
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