Boron Arylations of Subporphyrins with Aryl Zinc Reagents. Issue 10 (27th January 2016)

• Record Type: Journal Article
• Authors: Kotani, Ryota; Yoshida, Kota; Tsurumaki, Eiji; Osuka, Atsuhiro
• Is Part Of: Chemistry. Volume 22:Issue 10(2016)
• Page Start: 3320
• Page End: 3326
• Publication Date: 2016-01-27
• Subjects: boron–carbon bonds -- energy transfer -- organozinc reagents -- porphyrinoids -- subporphyrins; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201504719
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: Boron arylations of B‐ (methoxo)triphenylsubporphyrin have been developed with a combined use of ArZnI⋅LiCl and trimethylsilyl chloride. Aryl zinc reagents bearing bromo, cyano, amide, and ester groups can be employed for the B ‐arylation reaction to provide the corresponding B ‐arylated subporphyrins in moderate yields. Postmodifications of B ‐arylated subporphyrins have been demonstrated without loss of the B−C bond. These modifications include conversion of the cyano group into a benzoyl group with PhMgBr, hydrolysis of the ester group to give B ‐(4‐carboxyphenyl)subporphyrin, and Pd‐catalyzed Suzuki–Miyaura coupling of the 4‐bromophenyl group to give a 1, 4‐phenylene‐bridged subporphyrin–Zn II porphyrin hybrid that displays intramolecular excitation energy transfer from the subporphyrin to the porphyrin. The newly synthesized B ‐arylated subporphyrins have been fully characterized by NMR, UV/Vis absorption and fluorescence spectroscopies, mass spectrometry, electrochemical measurements, and X‐ray diffraction analysis. Abstract : Bonding B to C : Boron arylations of B‐ (methoxo)triphenylsubporphyrin have been developed with a combined use of ArZnI⋅LiCl and trimethylsilyl chloride (TMSCl; see scheme), which allow the synthesis of B ‐aryl subporphyrins bearing bromo, cyano, amide, and ester groups. Postmodifications of the B ‐aryl subporphyrins have been demonstrated without loss of the B−C bond. Newly synthesized B ‐arylated subporphyrins have been fully characterized.