Catalyst for ring expansion metathesis polymerization of cyclic monomers

Patent metadata

Field	Value
Publication number	US-11241681-B2
Application number	US-202016806054-A
Country	US
Kind code	B2
Filing date	Mar 2, 2020
Priority date	Sep 18, 2015
Publication date	Feb 8, 2022
Grant date	Feb 8, 2022

Abstract

A tetraanionic OCO pincer ligand metal-oxo-alkylidene complex is prepared from a trianionic pincer ligand supported metal-alkylidyne. The metal can be tungsten or other group 5-7 transition metal. The tetraanionic pincer ligand metal-oxo-alkylidene complex, a trianionic OCO pincer ligand metal complex, or a trianionic ONO pincer ligand metal complex can be used to polymerize cycloalkenes. The poly(cycloalkene)s are predominantly cis-alkene macrocyclics.

First claim

We claim:

1. A stereoregular cyclic polynorbornene consisting of repeating units having greater than 95% cis content and greater than 95% syndiotactic content.

2. The stereoregular cyclic polynorbornene according to claim 1 , wherein the degree of polymerization is 3 to 100,000.

3. The stereoregular cyclic polynorbornene according to claim 1 , wherein the stereoregular cyclic polynorbornene comprises double bonds and at least one of the double bonds is a reduced double bond.

4. The stereoregular cyclic polynorbornene according to claim 1 , wherein the stereoregular cyclic polynorbornene is a reduced cyclic poly(norbornene), wherein the reduced cyclic poly(norbornene) is prepared by reduction of one or more double bonds of a cyclic poly(cycloalkene).

5. A method of preparing the stereoregular cyclic polynorbornene of claim 1 , comprising
providing a catalytic initiator selected from a tetraanionic OCO pincer ligand supported metal-alkylidene complex, a trianionic OCO pincer ligand metal complex, or a trianionic ONO pincer ligand metal complex;
providing a plurality of norbornene monomers; and
combining the catalytic initiator with the norbonene monomers,
polymerizing the plurality of norbornene monomers into the stereoregular cyclic polynorbornene.

6. The method of claim 5 , wherein the tetraanionic OCO pincer ligand metal-alkylidene complex has the structure:

7. The method of claim 5 , wherein the trianionic OCO pincer ligand metal complex has the structure:

8. The method of claim 5 , wherein the trianionic ONO pincer ligand metal complex has the structure:

9. The method of claim 5 , further comprising a step of reducing one or more double bonds of the stereoregular cyclic polynorbornene, thereby forming a macrocyclic poly(norbornane).

10. The method of claim 5 , wherein the tetraanionic OCO pincer ligand supported metal-alkylidene complex has the structure selected from the group of:

Assignees

• Univ Florida

Inventors

• Veige Adam S
• Almeida Gonsales Stella

Classifications

• C07F11/00 Primary

  Compounds containing elements of Groups 6 or 16 of the Periodic Table · CPC title

• B01J31/2265

  Carbenes or carbynes, i.e.(image) · CPC title

• B01J31/2243

  At least one oxygen and one nitrogen atom present as complexing atoms in an at least bidentate or bridging ligand · CPC title

• B01J2531/0244

  Pincer-type complexes, i.e. consisting of a tridentate skeleton bound to a metal, e.g. by one to three metal-carbon sigma-bonds · CPC title

• B01J31/223 Primary

  At least two oxygen atoms present in one at least bidentate or bridging ligand · CPC title