The impact of the alkyne substitution pattern and metalation on the photo-isomerization of azobenzene-based platinum(II) diynes and polyynes

Rayya A. Al-Balushi, Ashanul Haque, Maharaja Jayapal, Mohammed K. Al-Suti, John Husband, Muhammad S. Khan, Jonathan M. Skelton, Kieran C. Molloy, Paul R. Raithby

Research output: Contribution to journalArticle

7 Citations (Scopus)
52 Downloads (Pure)

Abstract

Trimethylsilyl-protected di-alkynes incorporating azobenzene linker groups, Me3Si─C≡C─R─C≡C─SiMe3 (R = azobenzene-3,3’-diyl, azobenzene-4,4’-diyl, 2,5-bisoctylazobenzene-4,4’-diyl), and the corresponding terminal dialkynes, H─C≡C─R─C≡C─H, have been synthesised and characterized. The CuI-catalyzed dehydrohalogenation reaction between trans-[Ph(Et3P)2PtCl] and the deprotected dialkynes in a 2:1 ratio in iPr2NH/CH2Cl2 gives the Pt(II) di-ynes trans-[Ph(Et3P)2Pt─C≡C─R─C≡C─Pt(PEt3)2Ph], while the dehydrohalogenation polycondensation reaction between trans-[(nBu3P)2PtCl2] and the dialkynes in a 1:1 molar ratio under similar reaction conditions affords the Pt(II) poly-ynes, [─Pt(PnBu3)2─C≡C─R─C≡C─]n. The materials have been characterized spectroscopically, with the di-ynes also studied using single-crystal X-ray diffraction. The Pt(II) di-ynes and poly-ynes are all soluble in common organic solvents. Optical-absorption measurements show that the compounds incorporating the para-azobenzene spacer have a higher degree of electronic delocalisation than their meta-azobenzene counterparts. Reversible photoisomerization in solution was observed spectroscopically for the alkynyl-functionalised azobenzene ligands and, to a lesser extent, for the Pt(II) complexes. Complementary quantum-chemical modelling was also used to analyse the optical properties and the isomerisation energetics.
Original languageEnglish
Pages (from-to)10955–10967
Number of pages13
JournalInorganic Chemistry
Volume55
Issue number21
Early online date18 Oct 2016
DOIs
Publication statusPublished - 7 Nov 2016

Fingerprint

Diynes
Polyacetylenes
Photoisomerization
Alkynes
alkynes
Platinum
isomerization
platinum
Substitution reactions
substitutes
spacers
optical absorption
optical properties
ligands
single crystals
Polycondensation
Isomerization
electronics
diffraction
Organic solvents

Keywords

  • Azobenzene
  • Pt(II) acetylide complexes
  • Photoisomerisation
  • Time-dependent Density Functional Theory

Cite this

The impact of the alkyne substitution pattern and metalation on the photo-isomerization of azobenzene-based platinum(II) diynes and polyynes. / Al-Balushi, Rayya A.; Haque, Ashanul; Jayapal, Maharaja; Al-Suti, Mohammed K.; Husband, John; Khan, Muhammad S.; Skelton, Jonathan M.; Molloy, Kieran C.; Raithby, Paul R.

In: Inorganic Chemistry, Vol. 55, No. 21, 07.11.2016, p. 10955–10967.

Research output: Contribution to journalArticle

Al-Balushi, Rayya A. ; Haque, Ashanul ; Jayapal, Maharaja ; Al-Suti, Mohammed K. ; Husband, John ; Khan, Muhammad S. ; Skelton, Jonathan M. ; Molloy, Kieran C. ; Raithby, Paul R. / The impact of the alkyne substitution pattern and metalation on the photo-isomerization of azobenzene-based platinum(II) diynes and polyynes. In: Inorganic Chemistry. 2016 ; Vol. 55, No. 21. pp. 10955–10967.
@article{e91e78e402d24d8092408002de8edf98,
title = "The impact of the alkyne substitution pattern and metalation on the photo-isomerization of azobenzene-based platinum(II) diynes and polyynes",
abstract = "Trimethylsilyl-protected di-alkynes incorporating azobenzene linker groups, Me3Si─C≡C─R─C≡C─SiMe3 (R = azobenzene-3,3’-diyl, azobenzene-4,4’-diyl, 2,5-bisoctylazobenzene-4,4’-diyl), and the corresponding terminal dialkynes, H─C≡C─R─C≡C─H, have been synthesised and characterized. The CuI-catalyzed dehydrohalogenation reaction between trans-[Ph(Et3P)2PtCl] and the deprotected dialkynes in a 2:1 ratio in iPr2NH/CH2Cl2 gives the Pt(II) di-ynes trans-[Ph(Et3P)2Pt─C≡C─R─C≡C─Pt(PEt3)2Ph], while the dehydrohalogenation polycondensation reaction between trans-[(nBu3P)2PtCl2] and the dialkynes in a 1:1 molar ratio under similar reaction conditions affords the Pt(II) poly-ynes, [─Pt(PnBu3)2─C≡C─R─C≡C─]n. The materials have been characterized spectroscopically, with the di-ynes also studied using single-crystal X-ray diffraction. The Pt(II) di-ynes and poly-ynes are all soluble in common organic solvents. Optical-absorption measurements show that the compounds incorporating the para-azobenzene spacer have a higher degree of electronic delocalisation than their meta-azobenzene counterparts. Reversible photoisomerization in solution was observed spectroscopically for the alkynyl-functionalised azobenzene ligands and, to a lesser extent, for the Pt(II) complexes. Complementary quantum-chemical modelling was also used to analyse the optical properties and the isomerisation energetics.",
keywords = "Azobenzene, Pt(II) acetylide complexes, Photoisomerisation, Time-dependent Density Functional Theory",
author = "Al-Balushi, {Rayya A.} and Ashanul Haque and Maharaja Jayapal and Al-Suti, {Mohammed K.} and John Husband and Khan, {Muhammad S.} and Skelton, {Jonathan M.} and Molloy, {Kieran C.} and Raithby, {Paul R.}",
year = "2016",
month = "11",
day = "7",
doi = "10.1021/acs.inorgchem.6b01509",
language = "English",
volume = "55",
pages = "10955–10967",
journal = "Inorganic Chemistry",
issn = "0020-1669",
publisher = "American Chemical Society",
number = "21",

}

TY - JOUR

T1 - The impact of the alkyne substitution pattern and metalation on the photo-isomerization of azobenzene-based platinum(II) diynes and polyynes

AU - Al-Balushi, Rayya A.

AU - Haque, Ashanul

AU - Jayapal, Maharaja

AU - Al-Suti, Mohammed K.

AU - Husband, John

AU - Khan, Muhammad S.

AU - Skelton, Jonathan M.

AU - Molloy, Kieran C.

AU - Raithby, Paul R.

PY - 2016/11/7

Y1 - 2016/11/7

N2 - Trimethylsilyl-protected di-alkynes incorporating azobenzene linker groups, Me3Si─C≡C─R─C≡C─SiMe3 (R = azobenzene-3,3’-diyl, azobenzene-4,4’-diyl, 2,5-bisoctylazobenzene-4,4’-diyl), and the corresponding terminal dialkynes, H─C≡C─R─C≡C─H, have been synthesised and characterized. The CuI-catalyzed dehydrohalogenation reaction between trans-[Ph(Et3P)2PtCl] and the deprotected dialkynes in a 2:1 ratio in iPr2NH/CH2Cl2 gives the Pt(II) di-ynes trans-[Ph(Et3P)2Pt─C≡C─R─C≡C─Pt(PEt3)2Ph], while the dehydrohalogenation polycondensation reaction between trans-[(nBu3P)2PtCl2] and the dialkynes in a 1:1 molar ratio under similar reaction conditions affords the Pt(II) poly-ynes, [─Pt(PnBu3)2─C≡C─R─C≡C─]n. The materials have been characterized spectroscopically, with the di-ynes also studied using single-crystal X-ray diffraction. The Pt(II) di-ynes and poly-ynes are all soluble in common organic solvents. Optical-absorption measurements show that the compounds incorporating the para-azobenzene spacer have a higher degree of electronic delocalisation than their meta-azobenzene counterparts. Reversible photoisomerization in solution was observed spectroscopically for the alkynyl-functionalised azobenzene ligands and, to a lesser extent, for the Pt(II) complexes. Complementary quantum-chemical modelling was also used to analyse the optical properties and the isomerisation energetics.

AB - Trimethylsilyl-protected di-alkynes incorporating azobenzene linker groups, Me3Si─C≡C─R─C≡C─SiMe3 (R = azobenzene-3,3’-diyl, azobenzene-4,4’-diyl, 2,5-bisoctylazobenzene-4,4’-diyl), and the corresponding terminal dialkynes, H─C≡C─R─C≡C─H, have been synthesised and characterized. The CuI-catalyzed dehydrohalogenation reaction between trans-[Ph(Et3P)2PtCl] and the deprotected dialkynes in a 2:1 ratio in iPr2NH/CH2Cl2 gives the Pt(II) di-ynes trans-[Ph(Et3P)2Pt─C≡C─R─C≡C─Pt(PEt3)2Ph], while the dehydrohalogenation polycondensation reaction between trans-[(nBu3P)2PtCl2] and the dialkynes in a 1:1 molar ratio under similar reaction conditions affords the Pt(II) poly-ynes, [─Pt(PnBu3)2─C≡C─R─C≡C─]n. The materials have been characterized spectroscopically, with the di-ynes also studied using single-crystal X-ray diffraction. The Pt(II) di-ynes and poly-ynes are all soluble in common organic solvents. Optical-absorption measurements show that the compounds incorporating the para-azobenzene spacer have a higher degree of electronic delocalisation than their meta-azobenzene counterparts. Reversible photoisomerization in solution was observed spectroscopically for the alkynyl-functionalised azobenzene ligands and, to a lesser extent, for the Pt(II) complexes. Complementary quantum-chemical modelling was also used to analyse the optical properties and the isomerisation energetics.

KW - Azobenzene

KW - Pt(II) acetylide complexes

KW - Photoisomerisation

KW - Time-dependent Density Functional Theory

UR - http://www.scopus.com/inward/record.url?scp=84994491986&partnerID=8YFLogxK

U2 - 10.1021/acs.inorgchem.6b01509

DO - 10.1021/acs.inorgchem.6b01509

M3 - Article

VL - 55

SP - 10955

EP - 10967

JO - Inorganic Chemistry

JF - Inorganic Chemistry

SN - 0020-1669

IS - 21

ER -