US009 169178B2 (12) United States Patent (10) Patent No.: US 9,169,178 B2 Oren (45) Date of Patent: Oct. 27, 2015 (54) MANUFACTURING OF STABILIZED (52) U.S. Cl. PROPARGYL BROMIDE CPC ................ C07C 17/16 (2013.01); A0IN 29/02 (2013.01); C07C 17/42 (2013.01) (71) Applicant: BROMINE COMPOUNDS LTD., Beer (58) Field of Classification Search Sheva (IL) CPC ......... C07C 17/16; C07C 17/42: A01N 29/02 See application file for complete search history. (72) Inventor: Jakob Oren, Nesher (IL) (56) References Cited (73) Assignee: Bromine Compounds Ltd., Beer Sheva (IL) U.S. PATENT DOCUMENTS (*) Notice: Subject to any disclaimer, the term of this 6,291,731 B1* 9/2001 Stamm .................... C07. patent is extended or adjusted under 35 6,777.375 B2 8/2004 Magin et al. U.S.C. 154(b) by 0 days. 6.825,390 B1 1 1/2004 Herndon 2004/0044259 A1 3/2004 Mero ...................... CO7C 17/16 (21) Appl. No.: 14/429,817 570.261 (22) PCT Filed: Sep. 16, 2013 FOREIGN PATENT DOCUMENTS (86). PCT No.: PCT/L2O13AOSO784 GB 942348 11, 1963 S371 (c)(1), OTHER PUBLICATIONS (2) Date: Mar. 20, 2015 International Search Report from PCT/IL2013/050784: 2 pages; (87) PCT Pub. No.: WO2014/045278 mailed Sep. 1, 2014. PCT Pub. Date: Mar. 27, 2014 * cited by examiner (65) Prior Publication Data Primary Examiner — Shailendra Kumar US 2015/0225318A1 Aug. 13, 2015 (74) Attorney, Agent, Or Firm — Roach Brown McCarthy & Gruber, P.C.; Kevin D. McCarthy Related U.S. Application Data (60) Provisional application No. 61/704,586, filed on Sep. (57) ABSTRACT 24, 2012. This invention provides a process for obtaining propargyl bromide in high yield from propargyl alcohol and phosphorus (51) Int. Cl. bromide, in the form of a stable composition with alkylbro C07C 17/16 (2006.01) mide. AOIN 29/02 (2006.01) C07C 17/42 (2006.01) 18 Claims, No Drawings US 9, 169,178 B2 1. 2 MANUFACTURING OF STABILIZED starts, and a precursor of such alkylhalogenide which can be PROPARGYL BROMIDE brominated by PBr to provide the desired alkylhalogenide. The alkylhalogenide will usually include halogenated paraf This application is a 371 of PCT/IL13/50784, filed Sep. 16, fins having from 1 to 5 carbon atoms in the molecule, the 2013, which claims benefit of 61/704,586, filed Sep. 24, 5 precursor will usually include aliphatic alcohols having from 2012. 3 to 5 carbon atoms in the molecule. The precursor will usually comprise a lower aliphatic alcohol like propanol or FIELD OF THE INVENTION butanol, which will be brominated to the desired bromoal kane having the desired boiling point. In one aspect, the The present invention relates to an industrial process for 10 process according to the invention will comprise steps of i) manufacturing propargyl bromide in a good yield and in a mixing PA, an amine additive, and alkylhalogenide solvent stable form. having a boiling point between 55 and 110° C.; ii) adding PBr; iii) stirring the reaction mixture, and allowing said PBr BACKGROUND OF THE INVENTION to react with said PA, whereby obtaining a mixture containing 15 raw propargyl bromide and AH; and iv) washing and distilling Methyl bromide is an effective fumigant used in control said mixture in any order; thereby obtaining a stable compo ling a large variety of soilborne pests. As methyl bromide is an sition containing propargyl bromide and alkylhalogenide. In oZone depleting agent, and further it is relatively toxic for other aspect of the invention, the process according to the humans, its use has been gradually reduced, and the demands invention will comprise i) mixing PA, an amine additive, and for alternative pesticides have been increasing. A promising an aliphatic alcohol having between 3 and 5 carbon atoms; ii) alternative for methyl bromide is 3-bromopropyne, usually adding PBr. whereby obtaining a reaction mixture; iii) stir called propargyl bromide (PB). PB may be prepared by the ring said reaction mixture and allowing said PBr to react with reaction of propargyl alcohol with PBr in the presence of said PA to provide PB, and with said alcohol to provide alkyl pyridine, but the selectivity and yield of the reaction are low. bromide (AB), wherein said AB has a boiling point between U.S. Pat. No. 6,794.551 improved the process by controlling 25 55 and 110°C.; and iv) washing and distilling said mixture in temperature and effecting the reaction under an inert atmo any order, thereby obtaining a stable composition containing sphere without the presence of a base. Another problem about propargyl bromide and alkyl bromide. In a preferred embodi PB is its high flammability, and its vapors may form explosive ment, a method according to the invention comprises i) com mixtures with air. Precariously, propargylbromide is a shock bining propargyl alcohol (PA), a tertiary amine, and an alky and temperature-sensitive material that may detonate. Sev 30 lhalogenide selected from chlorinated and/or brominated eral techniques addressed the problem and stabilized PB by alkanes having a boiling point between 55 and 110°C., at a admixing a solvent forming an azeotropic mixture with the temperature between 0 and 40°C.; ii) adding PBr; iii) stir PB (see WO2004/071192; U.S. Pat. No. 6,777,375; U.S. Pat. ring the mixture obtained in step iii) at a temperature between No. 6,825,390; U.S. Pat. No. 7,015.367). It is an object of the 25 and 50° C. for between 1 and 5 hours, whereby obtaining present invention to provide an industrial process for manu 35 a raw mixture containing PB and AH; iv) washing said raw facturing propargyl bromide in a stable form and in a good mixture of step iii) with water; and v) distilling said raw yield. mixture at lowered pressure at a temperature up to 60° C. It is another object of the present invention to provide a wherein said step of washing and said step of distilling may be composition comprising propargyl bromide in a Sufficiently performed in any order, thereby obtaining a stable composi high concentration for intended applications but without 40 tion containing propargyl bromide and alkyl halogenide. In being impact sensitive. other preferred embodiment, a method according to the It is still another object of the present invention to provide invention comprises i) combining PA, an amine additive, and a composition comprising propargyl bromide which is not an alkylbromide (AB) solvent having a boiling point between explosive on heating. 55 and 110°C.; ii) adding PBr whereby obtaining a reaction Other objects and advantages of present invention will 45 mixture; iii) stirring the reaction mixture of step ii), whereby appear as description proceeds. obtaining a raw mixture containing PB and AB; iv) washing said raw mixture of step iii) with water; and v) distilling said SUMMARY OF THE INVENTION raw mixture at lowered pressure at a temperature up to 60°C., wherein said step washing and said distilling may be per The invention provides a method for preparing a stable 50 formed in any order; thereby obtaining a stable composition propargyl bromide (PB) composition, comprisingi) combin containing propargyl bromide and alkyl bromide. Said amine ing propargyl alcohol (PA), an amine additive, and an alkyl additive is preferably a tertiary amine. Said stable composi halogenide (AH) source selected from halogenated paraffins tion, prepared by the method of the invention, usually com and aliphatic alcohols; ii) adding phosphorus tribromide prises from 30 to 80 wt % propargylbromide, and it usually (PBr) to the mixture of step i) whereby obtaining a reaction 55 comprises from 17 to 67 wt % alkylhalogenide, for example mixture; iii) stirring said reaction mixture and allowing said from 19 to 69 wt % alkylhalogenide. In one embodiment of PBr to react at least with said PA, whereby obtaining a the invention, the stable composition prepared by the method mixture containing raw PB and AH; and iv) washing the of the invention comprises from 50 to 80 wt % propargylbro mixture of step iii) and distilling it at lowered pressure, mide, and it usually comprises from 17 to 47 wt % alkylha wherein the steps of washing and distilling may be performed 60 logenide, for example from 19 to 49 wt % alkylhalogenide. in any order, said Washing comprising separating organic The total amount of propargylbromide and alkylhalogenide phase and discarding water phase; thereby obtaining a stable in said stable composition is preferably at least 90 wt %, for composition containing propargyl bromide and alkylhalo example at least 94 wt %, such as 95 wt % or more. genide. Said AH source will usually include aliphatic mate In one embodiment of the method according to the inven rials having from 1 to 5 carbon atoms in the molecule. The 65 tion, a process is provided comprising steps of i) mixing PA, term alkylhalogenide source aims at including both ready an amine additive, and alkylbromide solvent having a boiling alkylhalogenide added to the mixture before the reaction point between 55 and 110° C., and cooling the mixture to a US 9, 169,178 B2 3 4 temperature below 5° C. and adding dropwise PBr, under having boiling point not too different from the boiling point of stirring, while keeping the temperature between 0 and 40°C.; PB, formed in the reaction mixture during the reaction ii) allowing said PBr to react with said PA, whereby obtain together with the PB. When relating to the boiling point of a ing a mixture containing raw propargyl bromide and AH; and suitable alkylhalogenide, the boiling points of PB and said iii) washing and distilling said mixture in any order; thereby solvent are considered as too different when they differ by obtaining a stable composition containing propargyl bromide more than about 26° C.; a suitable solvent for the present and alkylhalogenide.