Method for preparing aminopropylsilanes

Patent metadata

Field	Value
Publication number	US-11440926-B2
Application number	US-201816603329-A
Country	US
Kind code	B2
Filing date	Feb 6, 2018
Priority date	Feb 6, 2018
Publication date	Sep 13, 2022
Grant date	Sep 13, 2022

Abstract

Aminopropylalkoxysilanes of the formula

H 2 N—CR 2 R 3 —CHR 1 —CH 2 —SiR 4 R 5 (OR 6 )  I,

are synthesized by hydrosilylating silazanes of the formulae

and mixtures thereof, in the presence of a catalyst containing rhodium and/or iridium compounds, and then reacted with alcohol to form an aminopropylalkoxysilane.

First claim

The invention claimed is:

1. A method for synthesizing a 3-aminopropylalkoxysilane of the formula I
H 2 N—CR 2 R 3 —CHR 1 —CH 2 —SiR 4 R 5 (OR 6 )  I,

comprising:
a) hydrosilylating a silazane of the formulae IVa or IVb

or a mixture thereof, in the presence of a catalyst A which comprises a rhodium compound, an iridium compound, or a mixture thereof to form a hydrosilylated product, and
b) reacting the hydrosilylated product from step a) with an alcohol of the formula V
R 6 —OH  V,

and recovering the 3-aminopropylalkoxysilane of the formula (I),
where
R 1 to R 3 independently of one another are hydrogen or a monovalent unsubstituted or substituted C 1 -C 20 hydrocarbon radical optionally bridged by hydrocarbon radicals, and wherein one or more methylene units in the hydrocarbon radical are optionally replaced by —O—, —CO—, —COO—, —OCO— or —OCOO—, —S— or NR x groups, provided that when two or more methylene groups are so replaced, they are non-adjacent,
R 4 and R 5 independently of one another are a monovalent unsubstituted or substituted C 1 -C 20 hydrocarbon radical optionally bridged by hydrocarbon radicals, and wherein one or more methylene units in the hydrocarbon radical are optionally replaced by —O—, —CO—, —COO—, —OCO— or —OCOO—, —S— or NR x groups, provided that when two or more methylene groups are so replaced, they are non-adjacent,
R 6 is a hydrocarbon radical having 1 to 8 carbon atoms, where one or more non-adjacent carbon atoms are optionally replaced by oxygen provided that when two or more carbon atoms are replaced by oxygen, the carbon atoms are non-adjacent, and
R x is a monovalent unsubstituted or substituted C 1 -C 20 hydrocarbon radical optionally bridged by hydrocarbon radicals, wherein one or more methylene units in the hydrocarbon radical are optionally replaced by —O—, —CO—, —COO—, —OCO— or —OCOO—, —S— groups, provided that when two or more methylene groups are so replaced, they are non-adjacent.

2. The method of claim 1 , wherein R 1 is hydrogen.

3. The method of claim 1 , wherein R 2 and R 3 independently of one another are hydrogen or a methyl group.

4. The method of claim 2 , wherein R 2 and R 3 independently of one another are hydrogen or a methyl group.

5. The method of claim 1 , wherein R 4 and R 5 independently of one another are monovalent unsubstituted C 1 -C 6 hydrocarbon radicals.

6. The method of claim 1 , wherein R 6 is a hydrocarbon radical having 1 to 4 carbon atoms.

7. The method of claim 1 , wherein the catalyst A comprises at least one Rh or iridium complex that is 4-coordinate or 6-coordinate.

8. The method of claim 7 , in which the Rh and iridium complexes have ligands selected from the group consisting of halide, hydrogen, BF 4 − , mono- or bidentate N, P, As or Sb, N-heterocyclic carbene or alkenyl ligands, carbon monoxide, and mixtures thereof.

9. A method for synthesizing a 3-aminopropylalkoxysilane of the formula I
H 2 N—CR 2 R 3 —CHR 1 —CH 2 —SiR 4 R 5 (OR 6 )  I,

comprising:
a) in a first step, reacting an olefinic amine of the formula II
H 2 N—CR 2 R 3 —CHR 1 ═CH 2   II

with a chlorosilane of the formula III
ClSiR 4 R 5 H  III,

forming a silazane mixture comprising silazanes of the formulae IVa and IVb

b) in a second step, hydrosilylating the silazane mixture obtained in step a) in the presence of a catalyst A which comprises a rhodium compound, an iridium compound, or a mixture thereof to form a hydrosilylated product, and
c) reacting the hydrosilylated product of step b) with an alcohol of the formula V
R 6 —OH  V,

where
R 1 to R 3 independently of one another are hydrogen or a monovalent unsubstituted or substituted C 1 -C 20 hydrocarbon radical optionally bridged by hydrocarbon radicals, and wherein one or more methylene units in the hydrocarbon radical are optionally replaced by —O—, —CO—, —COO—, —OCO— or —OCOO—, —S— or NR x groups, provided that when two or more methylene groups are so replaced, they are non-adjacent,
R 4 and R 5 independently of one another are a monovalent unsubstituted or substituted C 1 -C 20 hydrocarbon radical optionally bridged by hydrocarbon radicals, and wherein one or more methylene units in the hydrocarbon radical are optionally replaced by —O—, —CO—, —COO—, —OCO— or —OCOO—, —S— or NR x groups, provided that when two or more methylene groups are so replaced, they are non-adjacent,
R 6 is a hydrocarbon radical having 1 to 8 carbon atoms, where one or more non-adjacent carbon atoms are optionally replaced by oxygen, provided that when two or more carbon atoms are replaced by oxygen, the carbon atoms are non-adjacent, and
R x is a monovalent unsubstituted or substituted C 1 -C 20 hydrocarbon radical optionally bridged by hydrocarbon radicals, wherein one or more methylene units in the hydrocarbon radical are optionally replaced by —O—, —CO—, —COO—, —OCO— or —OCOO—, or —S— groups, provided that when two more methylene groups are so replaced, they are non-adjacent.

10. The method of claim 9 , in which, in the step a), at least 2 mole equivalents of olefinic amine of the formula II, based on chlorosilane of the formula III, are used, and where a biphasic liquid mixture formed during the reaction comprises a lower phase which contains the hydrochloride of the amine of the formula II and an upper phase which contains a silazane mixture comprising silanes of the formulae IVa and IVb, are separated from each other by phase separation prior to step b).

Assignees

• Wacker Chemie Ag

Inventors

• Fritz-Langhals Elke
• Weidner Richard

Classifications

• C07F7/20

  Purification, separation · CPC title

• C07F7/188 Primary

  by reactions involving the formation of Si-O linkages · CPC title

• B01J2531/822

  Rhodium · CPC title

• B01J31/22

  Organic complexes · CPC title

• C07F7/1888 Primary

  by reactions involving the formation of other Si-linkages, e.g. Si-N · CPC title