This disclosure contemplates N-phosphonomethyl glycine ester anhydrides as new compounds, as well as a process for producing such compounds. This disclosure also contemplates the use of such N-phosphonomethyl glycine ester anhydrides as herbicides and as aids in the harvesting of citrus fruit. Also disclosed are compositions containing the N-phosphonomethyl glycine ester anhydride as active ingredients, such composition being useful as herbicides and for aiding in the harvesting of citrus fruit.
This application is a continuation-in-part of application Ser. No. 630,392 filed Nov. 10, 1975, which is a continuation of application Ser. No. 362,712 filed May 22, 1973, now abandoned, which is a division of Ser. No. 170,388 filed Aug. 9, 1971, now U.S. Pat. No. 3,799,758 which is a continuation-in-part of application Ser. No. 123,057 filed Mar. 10, 1971, now abandoned.
Herbicidal compounds of the formula: ##STR1## in which R.sup.1 denotes an optionally substituted hydrocarbon radical, R denotes the hydrogen atom or has one of the meanings given for R.sup.1, R.sup.2 and R.sup.3 denote the hydrogen atom or are such that OR.sup.2 and OR.sup.3 are hydrolyzable groups; R.sup.4 denotes a hydrogen atom or a hydrogenolyzable group, and the agriculturally acceptable salts of these compounds.
The present invention relates to a herbicidal composition that is in the form of solid water dispersible granules (WDG) containing the compound N-phosphonomethylglycine (glyphosate acid) in an admixture with a surfactant that is comprised of one or more polyglycolethers, each having a waxy consistency, and each polyglycolether having a linear saturated alcohol having from about 10 to about 15 carbon atoms, which is ethoxylated with from about 30 to about 40 moles of ethylene oxide per mole of alcohol. This composition provides a combination of manufacturing and weed killing (i.e., herbicidal) advantages that heretofore have been unattainable with the use of either glyphosate acid or glyphosate in salt form. The present invention also relates to methods of using this composition and a process for preparing the WDG composition that comprises mixing the glyphosate acid with the surfactant and then extruding the mixture.
