Claims
- 1. A method for synthesizing a fungicide of the formula: ##STR10## comprising dehydrating 4-hydroxy-4,5-dimethyl-2-trimethylsilanyl-dihydrothiophene-3-carboxylic acid allylamide, Formula (II), ##STR11## by heating II in a high boiling, inert solvent: or by dehydrating II in the presence of a solvent and a weak acid or a mild dehydrating agent.
- 2. The method of claim 1 wherein the dehydration is carried out in a solvent in the presence of a weak acid or a mild dehydrating agent.
- 3. The method of claim 2 wherein the weak acid is oxalic acid, the dehydrating agent is acetic anhydride, and the solvent is dimethoxyethane or toluene.
- 4. The method of claim 1 wherein the dehydration is carried out by heating the reaction mixture in a high boiling, inert solvent.
- 5. The method of claim 4 wherein the solvent is xylene.
- 6. The method of claim 1 wherein Formula (II) is prepared by reacting 3-mercapto-2-butanone and N-allyl-3-trimethylsilylpropiolic amide.
- 7. The method of claim 6 wherein N-allyl-3-trimethylsilylpropiolic amide is prepared by reacting 3-trimethylsilylpropiolic acid with oxalyl chloride to form an intermediate acid chloride, removing the excess oxalyl chloride and reacting the acid chloride with allyl amine to form the amide.
- 8. The method of claim 6 wherein N-allyl-3-trimethylsilylpropiolic amide is prepared by (1) reacting trimethylsilylacetylene with a strong base, (2) adding allyl isocyanate, and (3) adding trimethylsilyl chloride.
- 9. The method of claim 6 wherein N-allyl-3-trimethylsilylpropiolic amide is prepared by reacting bis(trimethylsilyl)acetylene and allyl isocyanate in the presence of an acid catalyst.
RELATED APPLICATION
This is a conventional application based on U.S. patent application Ser. No. 60/088,398, filed Jun. 5, 1998.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
5486621 |
Phillion et al. |
Jan 1996 |
|
Foreign Referenced Citations (1)
Number |
Date |
Country |
WO 9307751 |
Apr 1993 |
WOX |