Photochromic four-coordinate N,C-chelate boron compounds

Published Date
Coordination Chemistry Reviews
March–April 2012, Vol.256(5):759–770, doi:10.1016/j.ccr.2011.11.009
Recent Developments in Organometallic Chemistry: 2012

Review

Author 

• Ying-Li Rao
• Hazem Amarne
• Suning Wang ^,

• Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada

Received 14 August 2011. Revised 9 November 2011. Accepted 10 November 2011. Available online 9 December 2011. 

Abstract

Four-coordinate organoboron compounds with a N,C-chelate backbone have been found recently to display an unusual photoisomerization phenomenon with a distinct change of color. The photoisomerization process is thermally reversible, enabling the potential use of this class of compounds as a new class of photo-responsive materials. This review provides an account of our recent investigation on the effect of substitution, π-conjugation and metal chelation on the photoisomerization process of the N,C-chelate organoboron compounds. The photoisomerization phenomenon of azobenzene-based organoboron compounds will also be presented.

Graphical abstract

Highlights

► Photoisomerization of azobenzene organoboron compounds. ► Photochromic phenyl-pyridyl (ppy) chelate boron compounds, the role of the mesityl groups, substitution and π-conjugation effect. ► Alternative photoisomerization pathways in photochromic B-ppy compounds. ► Polyboryl systems and heterocyclic chelate systems. ► Impact of metal chelation on photoisomerization.

Keywords

• Photochromic compounds
• Boron
• N,C-chelate
• Photoisomerization
• Metal coordination
• Organoboron

---

Fig. 1.

Scheme 1.

Chart 1.

Chart 2.

Scheme 2.

Fig. 2.

Fig. 3.

Chart 3.

Chart 4.

Fig. 4.

Chart 5.

Fig. 5.

Fig. 6.

Chart 6.

Fig. 7.

Chart 7.

Fig. 8.

Chart 8.

Fig. 9.

Fig. 10.

Chart 9.

Fig. 11.

Chart 10.

Fig. 12.

Fig. 13.

Fig. 14.

Chart 11.

Fig. 15.

Fig. 16.

Fig. 17.

• ⁎ 
  Corresponding author.
  
  

For further details log on website :
http://www.sciencedirect.com/science/article/pii/S0010854511002578