17573-59-0

Basic information

• Product Name: Biphenylene, 2-bromo-
• CAS NO: 17573-59-0
• Molecular Formula: C12H7Br
• Molecular Weight: 231.092
• Mol File: 17573-59-0.mol
• Article Data: 2

Chemical Properties

• CAS DataBase Reference: Biphenylene, 2-bromo-(CAS DataBase Reference)
• NIST Chemistry Reference: Biphenylene, 2-bromo-(17573-59-0)
• EPA Substance Registry System: Biphenylene, 2-bromo-(17573-59-0)

Safety Data

• Hazardous Substances Data: 17573-59-0(Hazardous Substances Data)

Upstream product

• 92-52-4 biphenyl 
• 109162-89-2 2-bromo-dibenziodolium; iodide 

Downstream Products

• 96695-01-1 3-methylbiphenylen-2-ylmethyltriphenylphosphonium bromide 
• 1026-55-7 2-phenylbiphenylene 
• 24926-97-4 2-Benzoyl-7-brom-biphenylen 

Relevant articles and documents

Cyclopropyl Group: An Excited-State Aromaticity Indicator?

The cyclopropyl (cPr) group, which is a well-known probe for detecting radical character at atoms to which it is connected, is tested as an indicator for aromaticity in the first ππ* triplet and singlet excited states (T1 and S1). Baird's rule says that the π-electron counts for aromaticity and antiaromaticity in the T1 and S1 states are opposite to Hückel's rule in the ground state (S0). Our hypothesis is that the cPr group, as a result of Baird's rule, will remain closed when attached to an excited-state aromatic ring, enabling it to be used as an indicator to distinguish excited-state aromatic rings from excited-state antiaromatic and nonaromatic rings. Quantum chemical calculations and photoreactivity experiments support our hypothesis; calculated aromaticity indices reveal that openings of cPr substituents on [4n]annulenes ruin the excited-state aromaticity in energetically unfavorable processes. Yet, polycyclic compounds influenced by excited-state aromaticity (e.g., biphenylene), as well as 4nπ-electron heterocycles with two or more heteroatoms represent limitations.