Yield:-

Reaction Conditions:

in tert-butyl methyl ether; pH=5.5 - 6.5;Product distribution / selectivity;

Steps:

2

General Method; Experimental Equipment and Procedure[0030] Round bottom 500ml 3 neck flask equipped with stirrer, dip tube (for introduction of DMA) and thermometer.[0031 ] The flask was charged with 300ml of MTBE (or MTBE mother liquor from previous run) phenoxyacid (about 80g) was added to the MTBE and the mixture stirred. Anhydrous DMA was then introduced with continued stirring. During the introduction of DMA the salt precipitates.[0032] The reaction was monitored by addition of small amounts of reaction mixture to water. When the mixture provides a pH of 8 and remains at this pH the reaction was considered complete. The product was filtered and dried at temperature not greater than 60°C. The mother liquor is made up with fresh MTBE, ready for the next batch.Experimental ResultsExample 2 - Dicamba/DMA Salt[0034] Dicamba tech grade was supplied by Novataris.The finished product had the following characteristics:? Assay 800 g/kg (average)? pH 5.5-6.5 (3% solution in H₂0)Dicamba content in mother liquor was <1 %. Product is extremely hydroscopic.

References:

WO2011/143690,2011,A1 Location in patent:Page/Page column 8