Photochromic hydrazone switches

Patent metadata

Field	Value
Publication number	US-11279677-B2
Application number	US-201916401942-A
Country	US
Kind code	B2
Filing date	May 2, 2019
Priority date	Nov 4, 2016
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

Provided herein are compounds for use as photochromic molecular switches having very long thermal isomerization half-lives and switchable fluorescence properties both in solution and the solid state.

First claim

What is claimed is:

1. A compound of Formula I or a salt thereof:

wherein
represents a double bond having either E or Z stereochemistry;
A is phenyl or naphthyl;
B is phenyl or pyridine-2-yl;
R is O—R′,
where:
R′ is azide, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, alkoxyalkyl, heteroalkyl, alkoxy, aryl, or heteroaryl,
where in the alkenyl and alkynyl groups for R′, the double or triple bond is not at the alpha-beta position in the alkenyl or alkynyl group;
R 1 and R 2 are independently, for each occurrence, selected from the group consisting of heterocyclyl, halo, alkylamino, dialkylamino, diphenyl amino, hydroxyl, nitro, cyano, carboxyl, carboxylalkyl and carboxamido; or
R and one of R 2 are optionally linked by a 3-8 carbon linker, which is optionally substituted;
n is 0, 1, 2, 3, 4 or 5; and
m is 0, 1, 2, 3, 4, 5, 6 or 7;
provided that when n and m are both 0, at least one of A and B is not phenyl.

2. The compound of claim 1 , wherein (R 1 ) n -A- is selected from the group consisting of 4-dialkylaminophenyl, naphth-2-yl, naphth-1-yl, and 6-dialkylaminonaphth-2-yl.

3. The compound of claim 1 , wherein (R 2 ) , —B— is selected from the group consisting of 4-dialkylaminophenyl and pyridine-2-yl.

4. The compound of claim 1 , wherein (R 1 ) n -A- is selected from the group consisting of 4-dialkylaminophenyl, naphth-2-yl, naphth-1-yl, and 6-dialkylaminonaphth-2-yl, and B is selected from the group consisting of phenyl and pyridine-2-yl.

5. The compound of claim 1 , wherein (R 2 ) m —B— is selected from the group consisting of 4-dialkylaminophenyl and pyridine-2-yl, and A is selected from the group consisting of phenyl, naphth-2-yl, and naphth-1-yl.

6. The compound of claim 1 , wherein R is OR′ and R′ is C 1-6 alkyl.

7. The compound of claim 1 , wherein represents a double bond having E or Z stereochemistry.

8. The compound of claim 1 of structure:

or a salt thereof,
wherein
each R 10 independently is hydrogen or alkyl;
R is OR′ and R′ is C 1-6 alkyl.

9. The compound of claim 8 , of structure:

or a salt thereof.

10. The compound of claim 1 of structure:

or a salt thereof, wherein R is OR′ and R′ is C 1-6 alkyl.

11. A molecular switch comprising a compound of claim 1 .

12. A method of optically switching a compound of Formula I, or a salt thereof, or a material comprising the compound of Formula I or a salt thereof:

wherein
represents a double bond having either E or Z stereochemistry;
A is phenyl or naphthyl;
B is phenyl or pyridine-2-yl;
R is O—R′,
where:
each R′ is independently azide, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, alkoxyalkyl, heteroalkyl, alkoxy, aryl, or heteroaryl,
where in the alkenyl and alkynyl groups for R′, the double or triple bond is not at the alpha-beta position in the alkenyl or alkynyl group;
R 1 and R 2 are independently, for each occurrence, selected from the group consisting of heterocyclyl, halo, alkylamino, dialkylamino, diphenyl amino, hydroxyl, nitro, cyano, carboxyl, carboxylalkyl and carboxamido; or
R and one of R 2 are optionally linked by a 3-8 carbon linker, which is optionally substituted;
n is 0, 1, 2, 3, 4 or 5; and
m is 0, 1, 2, 3, 4, 5, 6 or 7;
provided that when n and m are both 0, at least one of A and B is not phenyl;
the method comprising irradiating said compound or material, thereby isomerizing the compound from the E stereoisomer to the Z stereoisomer, isomerizing the compound from the Z stereoisomer to the E stereoisomer.

13. The compound of claim 1 of structure selected from:

Assignees

• Dartmouth College

Inventors

• Abrahamian Ivan
• Qian Hai
• Pramanik Susnata
• Shao Baihao
• Li Quan

Classifications

• B82Y10/00

  Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic · CPC title

• C09K9/02

  Organic tenebrescent materials · CPC title

• C07D215/40 Primary

  attached in position 8 · CPC title

• C07C251/00

  Compounds containing nitrogen atoms doubly-bound to a carbon skeleton (diazo compounds C07C245/12) · CPC title

• C07B2200/09

  Geometrical isomers · CPC title