Patents by Inventor Ronald B. Leng

Ronald B. Leng has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 12017993
    Abstract: Methods for preparing 5-fluoro-6-(bromo or chloro)picloram analogs, or derivatives thereof, from picloram acid, picloram ester, or the nitrile analog of picloram are provided. The methods include chemical process steps that: (1) introduce a phthaloyl group onto the 4-amino substituent of picloram acid, picloram ester, or the nitrile analog of picloram, (2) add 2 fluorine atoms at the 5,6-positions of the pyridine ring using halex fluorination chemistry, (3) remove the phthaloyl group, hydrolyze the ester or nitrile substituent, and add chlorine or bromine to the 6-position by treatment with an acid and water, and finally, (4) esterify the 5-fluoro-6-(bromo or chloro)picloram acid produced in step (3) to a 5-fluoro-6-(bromo or chloro)picloram ester.
    Type: Grant
    Filed: June 23, 2022
    Date of Patent: June 25, 2024
    Assignee: CORTEVA AGRISCIENCE LLC
    Inventors: Jayachandran Devaraj, Nugzar Ghavtadze, Nicholas M. Irvine, Jeremy Kister, Melissa Lee, Ronald B. Leng, Rongrong [Mandy] Lin, Rong Ling, Noormohamed M. Niyaz, Abraham D. Schuitman, Aaron A. Shinkle, Siyu Tu, Gregory T. Whiteker, Chunming Zhang
  • Publication number: 20230174490
    Abstract: The present disclosure relates to improved methods of synthesizing 6-aryl-4-aminopicolinates, such as arylalkyl and alkyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates.
    Type: Application
    Filed: March 17, 2021
    Publication date: June 8, 2023
    Applicant: CORTEVA AGRISCIENCE LLC
    Inventors: CHUNMING ZHANG, SIYU TU, RONALD B. LENG, NICHOLAS IRVINE, ABRAHAM SCHUITMAN, AARON SHINKLE, JAYACHANDRAN DEVARAJ, CHENGLI ZU
  • Publication number: 20220371997
    Abstract: Methods for preparing 5-fluoro-6-(bromo or chloro)picloram analogs, or derivatives thereof, from picloram acid, picloram ester, or the nitrile analog of picloram are provided. The methods include chemical process steps that: (1) introduce a phthaloyl group onto the 4-amino substituent of picloram acid, picloram ester, or the nitrile analog of picloram, (2) add 2 fluorine atoms at the 5,6-positions of the pyridine ring using halex fluorination chemistry, (3) remove the phthaloyl group, hydrolyze the ester or nitrile substituent, and add chlorine or bromine to the 6-position by treatment with an acid and water, and finally, (4) esterify the 5-fluoro-6-(bromo or chloro)picloram acid produced in step (3) to a 5-fluoro-6-(bromo or chloro)picloram ester.
    Type: Application
    Filed: June 23, 2022
    Publication date: November 24, 2022
    Applicant: CORTEVA AGRISCIENCE LLC
    Inventors: JAYACHANDRAN DEVARAJ, NUGZAR GHAVTADZE, NICHOLAS M. IRVINE, JEREMY KISTER, MELISSA LEE, RONALD B. LENG, RONGRONG [MANDY] LIN, RONG LING, NOORMOHAMED M. NIYAZ, ABRAHAM D. SCHUITMAN, AARON A. SHINKLE, SIYU TU, GREGORY T. WHITEKER, CHUNMING ZHANG
  • Patent number: 11401242
    Abstract: Methods for preparing 5-fluoro-6-(bromo or chloro)picloram analogs, or derivatives thereof, from picloram acid, picloram ester, or the nitrile analog of picloram are provided. The methods include chemical process steps that: (1) introduce a phthaloyl group onto the 4-amino substituent of picloram acid, picloram ester, or the nitrile analog of picloram, (2) add 2 fluorine atoms at the 5,6-positions of the pyridine ring using halex fluorination chemistry, (3) remove the phthaloyl group, hydrolyze the ester or nitrile substituent, and add chlorine or bromine to the 6-position by treatment with an acid and water, and finally, (4) esterify the 5-fluoro-6-(bromo or chloro)picloram acid produced in step (3) to a 5-fluoro-6-(bromo or chloro)picloram ester.
    Type: Grant
    Filed: September 18, 2019
    Date of Patent: August 2, 2022
    Assignee: Corteva Agriscience LLC
    Inventors: Jayachandran Devaraj, Nugzar Ghavtadze, Nicholas M. Irvine, Jeremy Kister, Melissa Lee, Ronald B. Leng, Rongrong [Mandy] Lin, Rong Ling, Noormohamed M. Niyaz, Abraham D. Schuitman, Aaron A. Shinkle, Siyu Tu, Gregory T. Whiteker, Chunming Zhang
  • Publication number: 20220041574
    Abstract: This application relates to efficient and economical synthetic chemical processes for the preparation of pesticidal thioethers. Specifically, the present application relates to improved reactive crystallization methods for producing compounds useful in the preparation of pesticidal thioethers.
    Type: Application
    Filed: October 20, 2021
    Publication date: February 10, 2022
    Applicant: CORTEVA AGRISCIENCE LLC
    Inventors: DEBOLEENA CHAKRABORTY, XIAOYONG LI, TODD WILLIAM TOYZAN, RONALD B. LENG
  • Publication number: 20210323923
    Abstract: Methods for preparing 5-fluoro-6-(bromo or chloro)picloram analogs, or derivatives thereof, from picloram acid, picloram ester, or the nitrile analog of picloram are provided. The methods include chemical process steps that: (1) introduce a phthaloyl group onto the 4-amino substituent of picloram acid, picloram ester, or the nitrile analog of picloram, (2) add 2 fluorine atoms at the 5,6-positions of the pyridine ring using halex fluorination chemistry, (3) remove the phthaloyl group, hydrolyze the ester or nitrile substituent, and add chlorine or bromine to the 6-position by treatment with an acid and water, and finally, (4) esterify the 5-fluoro-6-(bromo or chloro)picloram acid produced in step (3) to a 5-fluoro-6-(bromo or chloro)picloram ester.
    Type: Application
    Filed: September 18, 2019
    Publication date: October 21, 2021
    Applicant: Corteva Agriscience LLC
    Inventors: Jayachandran Devaraj, Nugzar Ghavtadze, Nicholas M. Irvine, Jeremy Kister, Melissa Lee, Ronald B. Leng, Rongrong [Mandy] Lin, Rong Ling, Noormohamed M. Niyaz, Abraham D. Schuitman, Aaron A. Shinkle, Siyu Tu, Gregory T. Whiteker, Chunming Zhang
  • Publication number: 20200071290
    Abstract: This application relates to efficient and economical synthetic chemical processes for the preparation of pesticidal thioethers. Specifically, the present application relates to improved reactive crystallization methods for producing compounds useful in the preparation of pesticidal thioethers.
    Type: Application
    Filed: May 24, 2018
    Publication date: March 5, 2020
    Applicant: Dow AgroSciences LLC
    Inventors: Deboleen Chakraborty, Xiaoyong Li, Todd William Toyzan, Ronald B Leng
  • Patent number: 10570114
    Abstract: Improved methods of synthesizing 6-aryl-4-aminopicolinates, such as arylalkyl and alkyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates and arylalkyl and alkyl 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates, are described herein. The improved methods include a direct Suzuki coupling step, which eliminates the protection/de-protection steps in the current chemical process, and therefore eliminates or reduces various raw materials, equipment and cycle time as well as modification of other process conditions including use of crude AP, use of ABA-diMe, and varying pH, catalyst concentration, solvent composition, and/or workup procedures. This includes synthesis of 2-aryl-6-aminopyrimidine-4-carboxylates.
    Type: Grant
    Filed: July 26, 2018
    Date of Patent: February 25, 2020
    Assignee: Dow AgroSciences LLC
    Inventors: Jason S. Fisk, Xiaoyong Li, Mark Muehlfeld, Robert S. Bauman, Jossian Oppenheimer, Siyu Tu, Mark A. Nitz, Reetam Chakrabarti, Shawn D. Feist, James W. Ringer, Ronald B. Leng
  • Patent number: 10544121
    Abstract: Improved methods of synthesizing 6-aryl-4-aminopicolinates, such as arylalkyl and alkyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates and arylalkyl and alkyl 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates, are described herein. The improved methods include a direct Suzuki coupling step, which eliminates the protection/de-protection steps in the current chemical process, and therefore eliminates or reduces various raw materials, equipment and cycle time as well as modification of other process conditions including use of crude AP, use of ABA-diMe, and varying pH, catalyst concentration, solvent composition, and/or workup procedures. This includes synthesis of 2-aryl-6-aminopyrimidine-4-carboxylates.
    Type: Grant
    Filed: July 26, 2018
    Date of Patent: January 28, 2020
    Assignee: Dow AgroSciences LLC
    Inventors: Jason S. Fisk, Xiaoyong Li, Mark Muehlfeld, Robert S. Bauman, Jossian Oppenheimer, Siyu Tu, Mark A. Nitz, Reetam Chakrabarti, Shawn D. Feist, James W. Ringer, Ronald B. Leng
  • Patent number: 10407391
    Abstract: A method of preparing benzyl 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)picolinate (I) from benzyl 4,5-difluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)picolinate (II) is described. The method includes the use of amination and chlorination process steps to provide the compound of Formula I.
    Type: Grant
    Filed: December 6, 2017
    Date of Patent: September 10, 2019
    Assignee: Dow AgroSciences LLC
    Inventors: Jason S. Fisk, David J. Couling, Abraham D. Schuitman, Megan E. Donaldson, Brian Murdoch, Ronald B. Leng
  • Publication number: 20180334445
    Abstract: Improved methods of synthesizing 6-aryl-4-aminopicolinates, such as arylalkyl and alkyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates and arylalkyl and alkyl 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates, are described herein. The improved methods include a direct Suzuki coupling step, which eliminates the protection/de-protection steps in the current chemical process, and therefore eliminates or reduces various raw materials, equipment and cycle time as well as modification of other process conditions including use of crude AP, use of ABA-diMe, and varying pH, catalyst concentration, solvent composition, and/or workup procedures. This includes synthesis of 2-aryl-6-aminopyrimidine-4-carboxylates.
    Type: Application
    Filed: July 26, 2018
    Publication date: November 22, 2018
    Applicant: Dow AgroSciences LLC
    Inventors: Jason S. F, Xiaoyong Li, Mark Muehlfeld, Robert S. Bauman, Jossian Oppenheimer, Siyu Tu, Mark A. Nitz, Reetam Chakrabarti, Shawn D. Feist, James W. Ringer, Ronald B. Leng
  • Publication number: 20180334444
    Abstract: Improved methods of synthesizing 6-aryl-4-aminopicolinates, such as arylalkyl and alkyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates and arylalkyl and alkyl 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates, are described herein. The improved methods include a direct Suzuki coupling step, which eliminates the protection/de-protection steps in the current chemical process, and therefore eliminates or reduces various raw materials, equipment and cycle time as well as modification of other process conditions including use of crude AP, use of ABA-diMe, and varying pH, catalyst concentration, solvent composition, and/or workup procedures. This includes synthesis of 2-aryl-6-aminopyrimidine-4-carboxylates.
    Type: Application
    Filed: July 26, 2018
    Publication date: November 22, 2018
    Applicant: Dow AgroSciences LLC
    Inventors: Jason S. Fisk, Xiaoyong Li, Mark Muehlfeld, Robert S. Bauman, Jooossian Oppenheimer, Siyu Tu, Mark A. Nitz, Reetam Chakrabarti, Shawn D. Feist, James W. Ringer, Ronald B. Leng
  • Patent number: 10087164
    Abstract: Improved methods of synthesizing 6-aryl-4-aminopicolinates, such as arylalkyl and alkyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates and arylalkyl and alkyl 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates, are described herein. The improved methods include a direct Suzuki coupling step, which eliminates the protection/de-protection steps in the current chemical process, and therefore eliminates or reduces various raw materials, equipment and cycle time as well as modification of other process conditions including use of crude AP, use of ABA-diMe, and varying pH, catalyst concentration, solvent composition, and/or workup procedures. This invention was expanded to include synthesis of 2-aryl-6-aminopyrimidine-4-carboxylates.
    Type: Grant
    Filed: May 19, 2017
    Date of Patent: October 2, 2018
    Assignee: Dow AgroSciences LLC
    Inventors: Jason S. Fisk, Xiaoyong Li, Mark Muehlfeld, Robert S. Bauman, Jossian Oppenheimer, Siyu Tu, Mark A. Nitz, Reetam Chakrabarti, Shawn D. Feist, James W. Ringer, Ronald B. Leng
  • Publication number: 20180162814
    Abstract: A method of preparing benzyl 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)picolinate (I) from benzyl 4,5-difluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)picolinate (II) is described. The method includes the use of amination and chlorination process steps to provide the compound of Formula I.
    Type: Application
    Filed: December 6, 2017
    Publication date: June 14, 2018
    Applicant: Dow AgroSciences LLC
    Inventors: Jason S. Fisk, David J. Couling, Abraham D. Schuitman, Megan E. Donaldson, Brian Murdoch, Ronald B. Leng
  • Publication number: 20170334878
    Abstract: Improved methods of synthesizing 6-aryl-4-aminopicolinates, such as arylalky and alkyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates and arylalkyl and alkyl 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates, are described herein. The improved methods include a direct Suzuki coupling step, which eliminates the protection/de-protection steps in the current chemical process, and therefore eliminates or reduces various raw materials, equipment and cycle time as well as modification of other process conditions including use of crude AP, use of ABA-diMe, and varying pH, catalyst concentration, solvent composition, and/or workup procedures. This invention was expanded to include synthesis of 2-aryl-6-aminopyrimidine-4-carboxylates.
    Type: Application
    Filed: May 19, 2017
    Publication date: November 23, 2017
    Applicant: Dow AgroSciences LLC
    Inventors: Jason S. Fisk, Xiaoyong Li, Mark Muehlfeld, Robert S. Bauman, Jossian Oppenheimer, Siyu Tu, Mark A. Nitz, Reetam Chakrabarti, Shawn D. Feist, James W. Ringer, Ronald B. Leng
  • Patent number: 9598356
    Abstract: Cyhalofop is prepared by coupling 2-(4-hydroxyphenoxy)propionic acid and 3,4-difluorobenzonitrile with base in a polar aprotic solvent in the presence of a phase-transfer catalyst.
    Type: Grant
    Filed: February 24, 2011
    Date of Patent: March 21, 2017
    Assignee: Dow AgroSciences LLC
    Inventors: Ronald B. Leng, Eric W. Otterbacher, Herbert N. Praay
  • Publication number: 20160340311
    Abstract: Methods for the recovery and/or reuse of palladium catalyst after a Suzuki coupling reaction in which two molecules are coupled are described.
    Type: Application
    Filed: May 20, 2016
    Publication date: November 24, 2016
    Applicant: Dow AgroSciences LLC
    Inventors: Sanjib Biswas, Reetam Chakrabarti, Lauren M. Huffman, Ronald B. Leng, Abraham D. Schuitman, Karin Spiers, Alan L. Stottlemyer, Jeffrey B. Epp
  • Patent number: 9464175
    Abstract: Brominated organic polymer solutions from a bromination reaction are devolatilized in a devolatilizing extruder. A starting organic polymer is brominated in solution to form a brominated polymer solution. This solution is combined with a second thermoplastic polymer to form a concentrated solution. The solvent and other volatile compounds are removed from the concentrated solution in a devolatilizing extruder to form a devolatilized polymer blend.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: October 11, 2016
    Assignee: Dow Global Technologies LLC
    Inventors: Eung Kyu Kim, Daniel A. Beaudoin, Mark A. Barger, Ronald B. Leng
  • Publication number: 20150329507
    Abstract: The invention disclosed in this document is related to the field of processes for the preparation of enamines wherein R1, R2, R3, R4, R5, and further information are disclosed herein.
    Type: Application
    Filed: July 24, 2015
    Publication date: November 19, 2015
    Applicant: DOW AGROSCIENCES LLC
    Inventors: Douglas C. Bland, Todd William Toyzan, Ronald B. Leng, James R. McConnell
  • Patent number: 9006379
    Abstract: A process to produce polycarbamate comprising providing urea in liquid form; and adding the urea in liquid form to a polyol in a reduced gradient profile to form polycarbamate product is provided. Also provided are: (a) a reaction product of the process and (b) an apparatus for operating the process.
    Type: Grant
    Filed: July 31, 2013
    Date of Patent: April 14, 2015
    Assignee: Dow Global Technologies LLC
    Inventors: Xinrui Yu, Yiyong He, Ronald B. Leng