4. Use of MIC/NaHSO3 solid adduct (reported 27 July 1976) instead of MIC demonstrated for carbaryl, aldicarb, methomyl, and carbofuran.

5. Conversion of methyl formamide to MIC over dehydrogenation catalyst (Sun Ventures & DuPont, 1976).

6. Review of 55 MIC patents between January 1944 and July 1979 reveal primary method of MIC production to be phosgenation of methylamine followed by either (a) HCl removal by some separation technology, or (b) HCl removal by reaction with an acid receptor.

7. NaOCN + dimethyl sulfate → MIC + sodium sulfate (cyanate process) (Deutsche Gold patent; operated by Sunko, June 1980).

June 1985: DuPont, given loss of availability of bulk MIC, develops methyl formamide oxidation process for MIC(g) production and integrates with continuous methomyl process for minimum MIC inventory.

11 August 1985: Accidental release of aldicarb oxime and methylene chloride in Miscellaneous Carbamates Unit (aldicarb plant) (Lead in part to new OSHA safety program for chemical plants and EPA Chemical Emergency Preparedness Program).

January 1986: FMC, given the loss of availability of bulk MIC, starts production of carbofuran (Furadan) (operated by UCC on old ethyl alcohol site) in Institute West Carbamoylation Center; production by isocyanate process (carbofuran phenol + methyl isocyanate → carbofuran).

1986: UCC updates MIC patent review (July 1979-December 1985); patent activity shifting to MIC “carriers”:

1. Phosgenation of methylamine followed by pyrolysis of methyl carbamoyl chloride (traditional route; little patent activity);

2. Phosgenation of ureas (Philagro);

3. Thermal decomposition of carbamic acid esters (Bayer, EniChemica);

4. Thermal decomposition of trisubstituted ureas (Bayer);

5. Thermal decomposition of oxazolidinones (Agency of Industrial Science and Technology);

6. Thermal decomposition of oxalamate (BASF);

7. Thermal decomposition of N-substituted acetylacetamides (Bayer);

8. Thermal decomposition of dialkylmalonamides (Bayer);

9. Thermal decomposition on N,N’-disubstituted allophanates (BASF);

10. Thermal decomposition of organosilicon intermediates (Soviet publications);

11. Thermal decomposition of reversible boron-MIC adducts (Vertac);

12. Dehydrogenation of N-methylformamide (DuPont);

13. Methylation of metal cyanate (Degussa, FMC);



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