Isomers of [12]Annulyne and their Reactive Relationships to Heptalene and Biphenyl

• Published in: Angewandte Chemie (International ed.) Vol. 47; no. 45; pp. 8714 - 8718
• Main Authors: Rose, Brad D, Reiter, Richard C, Stevenson, Cheryl D
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley-VCH Verlag 27.10.2008; WILEY-VCH Verlag; WILEY‐VCH Verlag; Wiley
• Subjects: Alkynes - chemistry; annulene; Biphenyl Compounds - chemistry; Chemistry; Chemistry, Multidisciplinary; Cycloheptanes - chemistry; Cycloparaffins - chemical synthesis; Cycloparaffins - chemistry; EPR spectroscopy; heptalene; Isomerism; Magnetic Resonance Spectroscopy; Models, Chemical; NMR spectroscopy; Physical Sciences; radical anions; Science & Technology; ELECTRON-SPIN-RESONANCE; annulene; radical anions; heptalene; ANION-RADICALS; NMR spectroscopy; EPR spectroscopy; BENZYNE
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.200803863

[12]Annulyne not like benzyne: The base‐initiated condensation of hexadiyne in nonpolar solvents leads directly to the symmetrical isomers of [12]annulyne, i.e. the all cis isomer, which exists as its cumulene, and the 6,9‐trans,trans isomer. One‐electron transfer to this mixture leads to the formation of an unsymmetrical [12]annulyne radical anion, which transfers an electron to the all cis system leading to the biphenyl radical anion, while reduction of the other isomer leads to heptalene (see scheme).