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US3758620A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the preparation of grignard reagents

Assignee: National Patent Development Corp
•
Filing: 1971-06-11
•
Granted: 1973-09-11
•
Expires: 1991-06-11
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Abstract

Abstract Homogeneous catalyst solvent systems for the preparation of Grignard reagents and the running of Grignard reactions are disclosed. These systems are superior to existing techniques for running Grignard reactions in that they significantly reduce or completely eliminate the induction periods which occur in most Grignard reagent ( RMgX; where R Alkyl or Aryl and X Cl,Br or I) preparations and make possible the use of alkyl chlorides in the Grignard preparations instead of the more expensive alkyl bromides or iodides. The catalyst solvent systems are formed by the addition of small percentages of reducing hydrides, for example, LiAlH4, NaAlH4, NaAlH2(OCH2CH2OCH3)2 or NaAlH (OCH2CH2OCH3)3, to the ether solvents, such as diethyl ether, tetrahydrofuran, dibutyl ether or 1,2 dimethoxyethane.

Inventors

  • 👤 J Vit

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 13:14
CPC Classifications
C; C07; C07F; C07F3/00; C07F3/02; C07D; C07D307/00; C07D307/02; C07D307/04; C07D307/10; C07D307/12

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 31 words
A method as claimed in claim 1 wherein the complex hydride is used in an amount corresponding to 0.005 to 0.1 gm of reducing hydrogen per liter of the ether solvent.
Claim 2
Dependent Claim 15 words
A method as claimed in claim 1 wherein the complex hydride is NaAlH(OCH2CH2OCH3)3 or NaAlH2(OCH2CH2OCH3)2.
Claim 3
Dependent Claim 21 words
A method as claimed in claim 1 wherein the ether solvent is diethyl ether, dibutyl ether, tetrahydrofuran, glyme, diglyme or dioxane.
Claim 4
Dependent Claim 20 words
A method as claimed in claim 1 wherein the organic halide is an alkyl or aryl chloride, bromide or iodide.
Claim 5
Dependent Claim 40 words
A method as claimed in claim 1 comprising first preparing the ether solvent by adding the complex hydride to the ether, then adding the magnesium metal to the ether solvent and thereafter adding the organic halide to the ether solvent.
Claim 6
Dependent Claim 33 words
A method as claimed in claim 1 comprising first adding the magnesium metal to the ether solvent, then adding the complex hydride thereto and finally adding the organic halide to the ether solvent.
Claim 7
Dependent Claim 28 words
A method as claimed in claim 7 wherein the complex hydride is added in the form of a concentrated solution thereof in said ether or an aromatic hydrocarbon.
Claim 8
Independent Claim 48 words
A method of activating magnesium metal for use in a Grignard reaction comprising adding magnesium metal to a composition consisting essentially of an ether solvent and a complex hydride of the formula Na Al H(OR)3 or NA Al H2(OR)2 wherein R is R'' O (CH2)n, or R''O(CH2)n-O-(CH2)m-, or
Claim 9
Dependent Claim 18 words
A method according to claim 9 wherein the complex hydride is Na Al H(OCH2CH2OCH3)2 or Na Al H2(OCH2CH2OCH3)2.
Claim 10
Dependent Claim 20 words
A method according to claim 9 wherein the ether solvent is diethyl ether, dibutyl ether, tetrahydrofuran, glyme, diglyme or dioxane.

References Cited (Backward Citations)

FR1515582A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-09-10 1977-03-12 1977-09-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-09-10 1981-03-12 1981-09-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-09-10 1985-03-12 1985-09-11 $7700.00 Window Closed / Lapsed

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