US3641081A - Process for preparing dialkylzinc compounds from alkylbromide - Google Patents

Process for preparing dialkylzinc compounds from alkylbromide Download PDF

Info

Publication number
US3641081A
US3641081A US792852*A US3641081DA US3641081A US 3641081 A US3641081 A US 3641081A US 3641081D A US3641081D A US 3641081DA US 3641081 A US3641081 A US 3641081A
Authority
US
United States
Prior art keywords
zinc
alloy
reaction
sodium
alkylbromide
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US792852*A
Other languages
English (en)
Inventor
Schrade F Radtke
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Lead Zinc Research Organization Inc
Original Assignee
International Lead Zinc Research Organization Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by International Lead Zinc Research Organization Inc filed Critical International Lead Zinc Research Organization Inc
Application granted granted Critical
Publication of US3641081A publication Critical patent/US3641081A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C18/00—Alloys based on zinc
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F3/00—Compounds containing elements of Groups 2 or 12 of the Periodic Table
    • C07F3/06—Zinc compounds

Definitions

  • This invention relates to a direct process for preparing dialkylzinc compounds.
  • Diorganic compounds are generally prepared by two methods.
  • the first method reacts a zinc halide with a reactive organometallic, such as lithium or magnesium, in an ether solvent.
  • the second method involves a direct synthesis starting from metallic zinc or zinc alloys with alkyl iodides. Mixtures of alkyl bromides and iodides have also previously been used in combination with zinccopper alloy.
  • the first method is disadvantageous in that it requires two separate steps to be performed. In the first step the lithium or magnesium reagent must be formed, and in the second step the actual formation of the organozinc compound takes place.
  • An additional disadvantage is the presence in the reaction of flammable solvents. The separation of the solvents from the product is not always ealiilly achieved, especially with the utilization of lower a ys.
  • the second method is more attractive in that only one step is required and the use of solvents is not necessary, although recent attempts to find improved conditions have utilized solvents with'high dielectric constants, such as dimethylformamide.
  • solvents with'high dielectric constants such as dimethylformamide.
  • the use of solvents makes it impossible to separate solvent from the product.
  • the reaction usually begins a few minutes after the starting materials have made contact with each other, especially if substantially all traces of moisture have been removed from the atmosphere and the apparatus. Heating of the reaction mixture may be necessary to begin the reaction, but if the reaction is exothermal refluxing temperature is maintained without the application of external heat. In the event that the reaction is not exothermal, external heating may be applied to maintain the reflux temperature. It has been found that a temperature in the range of 40-l80 C. is satisfactory. A temperature range of l00-l40 C. is preferred.
  • the reaction is considered complete when refluxing stops.
  • the flask is connected with a distilling head and the contents of the flask are distilled under reduced pressure. Distillation of the product mixture vaporizes the dialkylzinc compound which is captured as a distillation product.
  • the zinc alloys which have proved themselves reliable for purposes of the invention are the lithium, potassium and sodium alloys.
  • the alloys may be formed by fusing the metals together in a steel crucible under an inert atmosphere, for example, argon. The cooled melt is machined to fine particle size. Usually turnings may be used, but if the alloy is very brittle a sandlike material is obtained upon machining.
  • the shot method may also be utilized to prepare the alloys on an industrial scale.
  • the maximum amount of sodium which can be alloyed with zinc is one atom of sodium per twelve atoms of zinc. This corresponds with an alloy containing three wt. percent sodium, the balance being zinc.
  • Table I contains data showing the yield of dialkylzinc in relation to the percentage of sodium in the alloy.
  • Zinc alloyed with potassium is obtained by fusing zinc and potassium under an inert atmosphere, such as nitrogen, and machining in the usual way.
  • the alloy is very reactive and should be kept in an inert atmosphere.
  • the maximum amount of potassium in the zinc/potas sium alloy is approximately 5 wt. percent, which corresponds to a molar ratio of 12 moles zinc to 1 mole potassium. .
  • the reaction with the alkylbromide is carried out in the same manner as with the zinc/sodium alloy. Once begun, the reaction continues spontaneously upon addition of the bromide.
  • the potassium content of the alloy may be reduced without loss of activity.
  • the zinc/potassium alloys are easily handled and machined to small particle size.
  • the 2% potassium/zinc alloy is well suited for the direct synthesis of zinc dialkyls, although the yields in general are somewhat lower than for the zinc/ sodium alloys.
  • the recommended range would be 0.5-5.0 wt. percent potassium with 1.5 to 2.0 wt. percent potassium preferred.
  • a useful lithium range is 1 to wt. percent lithium in the zinc alloy, with a preferred content of approximately 2 wt. percent lithium.
  • Ternary alloys may be used to provide good yields of dialkylzinc compounds.
  • the amalgamation of the zinc/ sodium alloy by treating the 3% sodium/zinc alloy with HgCl in tetrahydrofuran provides approximately the same yield as using the zinc/sodium alloy without the Hgcl
  • An alloy composed of 2.6% sodium, 1.1% mercury and the rest zinc was reacted with butyl'brornide and yielded 52% dibutylzinc.
  • the synthesis according to the invention may be carried out with both normal and branched chain alkylbromides. Since longer chain dialkylzincs, for example, where R is greater than C have limited thermal stability, a direct synthesis involving thermal cracking of primarily formed RZnBr to give R Zn+ZnBr is not practical. At the other end of the scale, the boiling point of methyl bromide is low and requires reaction under higher pressure conditions than atmospheric pressure.
  • Hg contained some 2,7-dimethyloctane (the Wurtz coupling product of iso-amylbromide) as, appeared from a gas chromatoe graphic analysis of the hydrolysis products).
  • the yield of di-isoamylzinc after refractionation, B.P. 64-,689/ 2 mm.) was 5.48 g. (46% of theory).
  • EXAMPLE 5 I 1 n-Bu Zn from ZnK alloy (2% K) and n-BuBr A mixture of 29.0 g. of finely divided Zn-2.0 K. alloy (0.44 g. at. Zn) and 5.0 ml. of n-BuBr was gradually warmed up (to oil bath temp, of When reaction had started -18 ml. of n-BuBr (0.22 mole n"-BuBr.in total)v was added dropwise' After a further 30 min hea'ting period 10.8 g. n-Bu Zn (55% of theory) was isolated by distillation in vacuo.
  • a process for preparing dialkylzinc compounds comprising:
  • an alloy of zinc having at least one metal selected from the group consisting of sodium, potassium, and lithium, the amount of metal in the alloy being about 1 to about 3 weight percent sodium, about 0.5 to about 5.0 weight percent potassium and about 1 to about 10 weight percent lithium, with the remaining percentage being zinc, with (ii) a reagent consisting essentially of alkylbromide in a molar ratio of at least 1 to 1, zinc to alkylbromide, wherein the alkyl radical is selected from the group consisting of saturated and unsaturated alkyl radicals containing from 1 to -8 carbon atoms; and
  • alkylbromide is selected from the group consisting of methylbromide and ethylbromide, and the alkylbromide is re fiuxed under a pressure above that of atmospheric pressure.
  • dialkylzinc is added to the reaction mixture to remove traces of moisture.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
US792852*A 1969-01-21 1969-01-21 Process for preparing dialkylzinc compounds from alkylbromide Expired - Lifetime US3641081A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US79285269A 1969-01-21 1969-01-21

Publications (1)

Publication Number Publication Date
US3641081A true US3641081A (en) 1972-02-08

Family

ID=25158280

Family Applications (1)

Application Number Title Priority Date Filing Date
US792852*A Expired - Lifetime US3641081A (en) 1969-01-21 1969-01-21 Process for preparing dialkylzinc compounds from alkylbromide

Country Status (6)

Country Link
US (1) US3641081A (ja)
BE (1) BE733267A (ja)
DE (1) DE1925652A1 (ja)
FR (1) FR2028746A1 (ja)
GB (1) GB1243305A (ja)
NL (1) NL6907898A (ja)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4187254A (en) * 1976-11-09 1980-02-05 Societe Chimique Des Charbonnages - Cdf Chimie Grignard reagents and processes for making them
US4385003A (en) * 1981-10-30 1983-05-24 Stauffer Chemical Company Dialkylzinc composition having improved thermal stability
US4402880A (en) * 1981-10-30 1983-09-06 Stauffer Chemical Company Dialkylzinc compositions having improved thermal stability
US4407758A (en) * 1981-10-30 1983-10-04 Stauffer Chemical Company Dialkylzinc compositions having improved thermal stability
US6521771B2 (en) * 2000-05-19 2003-02-18 Goldschmidt Ag Use of zinc treated with metal hydride in organometallic synthesis
CN109128064A (zh) * 2018-09-21 2019-01-04 北京科技大学 一种可生物降解Zn-Na系锌合金及其制备方法

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4187254A (en) * 1976-11-09 1980-02-05 Societe Chimique Des Charbonnages - Cdf Chimie Grignard reagents and processes for making them
US4385003A (en) * 1981-10-30 1983-05-24 Stauffer Chemical Company Dialkylzinc composition having improved thermal stability
US4402880A (en) * 1981-10-30 1983-09-06 Stauffer Chemical Company Dialkylzinc compositions having improved thermal stability
US4407758A (en) * 1981-10-30 1983-10-04 Stauffer Chemical Company Dialkylzinc compositions having improved thermal stability
US6521771B2 (en) * 2000-05-19 2003-02-18 Goldschmidt Ag Use of zinc treated with metal hydride in organometallic synthesis
CN109128064A (zh) * 2018-09-21 2019-01-04 北京科技大学 一种可生物降解Zn-Na系锌合金及其制备方法
CN109128064B (zh) * 2018-09-21 2020-04-28 北京科技大学 一种可生物降解Zn-Na系锌合金及其制备方法

Also Published As

Publication number Publication date
GB1243305A (en) 1971-08-18
DE1925652A1 (de) 1970-10-01
NL6907898A (ja) 1970-07-23
FR2028746A1 (ja) 1970-10-16
BE733267A (ja) 1969-11-03

Similar Documents

Publication Publication Date Title
GB829574A (en) Method for the preparation of metallo-organic compounds
US3641081A (en) Process for preparing dialkylzinc compounds from alkylbromide
US2992248A (en) Processes for preparing halo group iii-a hydrides and halo group iii-a hydrocarbons
US2596690A (en) Preparation of boron compounds
US2921954A (en) Novel vinyl borons and method of preparation
US3641080A (en) Process for preparing dialkylizinc compounds from alkylbromide and alkyliodide
US2913498A (en) Process for preparing aromatic phosphorus compounds
US2838556A (en) Organo-aluminum compounds
US5211887A (en) High purity alkyllithium compounds and process of preparation
US4291167A (en) Preparation of tetramethyldisilane from 1,2-tetramethyldichlorodisilane
US2927124A (en) Preparation of trimethoxyboroxine
US4855523A (en) Catalyst and process for the selective dimerization of propylene to 4-methyl-1-pentene
US3052702A (en) Preparation of organolead compounds
US3155736A (en) Method of making organolithium compounds
US3047358A (en) Preparation of boron-hydrogen compounds
US2575760A (en) Preparation of heavy metal borohydrides
US2992072A (en) Preparation of diborane
US3045049A (en) Halogen containing organic derivatives of decaborane
US3397241A (en) Process for the economical preparation of br3 organoboron compounds
US5081231A (en) Uranium (III) catalyst for the selective dimerization of propylene to 4-methyl-1-pentene
US4960869A (en) Uranium allylic complex
US3647839A (en) Synthesis of tetramethyllead
US3401189A (en) Tetramethyl lead manufacture
US3389187A (en) Perfluoroisobutylene dimer
US3136795A (en) Manufacture of organolead compounds