Claims
- 1. A process for preparing a compound of the formula: ##STR6## wherein R.sup.2 is hydrogen or C.sub.1 -C.sub.6 alkyl optionally substituted by up to 3 substituents each independently selected from C.sub.1 -C.sub.6 alkoxy and C.sub.1 -C.sub.6 alkoxy(C.sub.1 -C.sub.6 alkoxy)-; and
- R.sup.3 is C.sub.1 -C.sub.6 alkyl or benzyl, said benzyl group being optionally ring-substituted by up to 2 nitro or C.sub.1 -C.sub.4 alkoxy substituents,
- comprising reacting a compound of the formula: ##STR7## wherein R.sup.1 is C.sub.1 -C.sub.4 alkyl, phenyl, benzyl or C.sub.1 -C.sub.4 alkoxy; and
- R.sup.2 and R.sup.3 are as previously defined for a compound of the formula (I), with hydrogen peroxide.
- 2. The process of claim 1 wherein said reacting step is carried out in a suitable solvent and in the presence of acid or base.
- 3. The process of claim 2 in which the solvent is tert-butanol.
- 4. The process of claim 2 in which the acid is a mineral acid.
- 5. The process of claim 4 in which the acid is sulphuric acid.
- 6. The process of claim 1 which is carried out in acetic acid.
- 7. The process of claim 2 in which the base is selected from the group consisting of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, or potassium bicarbonate.
- 8. The process of claim 7 in which the base is sodium bicarbonate or potassium bicarbonate.
- 9. The process of claim 1 wherein
- R.sup.1 is C.sub.1 -C.sub.4 alkyl, phenyl, or C.sub.1 -C.sub.4 alkoxy;
- R.sup.2 is hydrogen or C.sub.1 -C.sub.6 alkyl optionally substituted by one C.sub.1 -C.sub.6 alkoxy or C.sub.1 -C.sub.6 alkoxy(C.sub.1 -C.sub.6 alkoxy)- substituent; and
- R.sup.3 is C.sub.1 -C.sub.6 alkyl or benzyl, said benzyl group being optionally ring-substituted by one nitro or C.sub.1 -C.sub.4 alkoxy substituent.
- 10. The process of claim 9 in which
- R.sup.1 is methyl, phenyl or ethoxy;
- R.sup.2 is hydrogen, 2-methoxyethoxymethyl, 2-methoxyethyl or methoxymethyl; and
- R.sup.3 is ethyl, tert-butyl, benzyl, 4-nitrobenzyl or 4-methoxybenzyl.
- 11. The process of claim 10 in which
- R.sup.1 is methyl or ethoxy;
- R.sup.2 is hydrogen or 2-methoxyethoxymethyl; and
- R.sup.3 is tert-butyl.
- 12. The process of claim 1, further including conversion of the compound of formula (I) to a salt thereof.
Priority Claims (1)
Number |
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8907704 |
Apr 1989 |
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Parent Case Info
This is a division of application Ser. No. 08/286,054, filed on Aug. 4, 1994, now abandoned, which, in turn, is a continuation-in-part of application Ser. No. 08/120,706, filed on Sep. 13, 1993, now abandoned, which, in turn, is a continuation of application Ser. No. 07/747,770, filed Aug. 20, 1991, now abandoned, which, in turn, is a divisional application of application Ser. No. 07/504,493, filed Apr. 4, 1990, now U.S. Pat. No. 5,166,406.
US Referenced Citations (3)
Non-Patent Literature Citations (5)
Entry |
Chemical Abstracts, 28-Alicyclic Compounds, 57, No. 16424 (d) to No. 16426 (1962). |
E. Ritchie, et al., Aust. J. Chem., 17, 281 (1964). |
S. Dev., J. Indian Chem. Soc., 34 (4), 266 (1957). |
S. M. McElvain et al., J. Am. Chem. Soc., 81, 5590 (1959). |
B. W. Roberts, et al., J. Chem. Soc. Chem. Commun., 1980 (10) 428. |
Divisions (2)
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286054 |
Aug 1994 |
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Parent |
504493 |
Apr 1990 |
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Continuations (1)
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747770 |
Aug 1991 |
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Continuation in Parts (1)
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120706 |
Sep 1993 |
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