829-14-1

Basic information

• Product Name: 7,8,9,10-tetrahydrobenzo[8]annulen-5(6H)-one
• CAS NO: 829-14-1
• Molecular Formula: C₁₂H₁₄O
• Molecular Weight: 174.239
• Mol File: 829-14-1.mol
• Article Data: 1

Chemical Properties

• Boiling Point: 292.1°C at 760 mmHg
• Flash Point: 122.6°C
• Density: 1.035g/cm³
• Vapor Pressure: 0.00187mmHg at 25°C
• Refractive Index: 1.535
• CAS DataBase Reference: 7,8,9,10-tetrahydrobenzo[8]annulen-5(6H)-one(CAS DataBase Reference)
• NIST Chemistry Reference: 7,8,9,10-tetrahydrobenzo[8]annulen-5(6H)-one(829-14-1)
• EPA Substance Registry System: 7,8,9,10-tetrahydrobenzo[8]annulen-5(6H)-one(829-14-1)

Safety Data

• Hazardous Substances Data: 829-14-1(Hazardous Substances Data)

Upstream product

• 31274-15-4 1,3,4,8b-tetrahydrobiphenylen-4a(2H)-ol 

Downstream Products

• 6223-52-5 4,4-Dibrom-1,2-benzo-cycloocten-3,8-dion 
• 6223-53-6 3,3,8,8-Tetrabrom-1,2-benzocycloocten 
• 6223-47-8 2,3-Cyclopenteno-inden-1-on 
• 137376-70-6 6-Dimethylaminomethyl-7,8,9,10-tetrahydro-6H-benzocycloocten-5-one; hydrochloride 
• 108481-99-8 5,6,7,8-tetrahydro-4H-benzo[h]tetrazolo[1,5-a]azonine 
• 73424-48-3 5,6,7,8,9,10-Hexahydrobenzocycloocten-5-on-p-tolylsulfonylhydrazon 

Relevant articles and documents

Regioselectivity of the Base-Induced Ring Cleavage of 1-Oxygenated Derivatives of Cyclobutabenzene

Oxy anions 3 generated from 1,2-dihydrocyclobutabenzen-1-ones 1 through addition of a charged nucleophile or from 1-hydroxy-1,2-dihydrocyclobutabenzenes 2 by deprotonation with base lead to stable products through distal and/or proximal cleavage of the strained four-membered ring via benzyl carbanion 4 and/or aryl carbanion 5. A systematic study of this process reveals the relative stability of the two isomeric carbanions 4 and 5 as a key factor in determining the course of the ring-cleavage reaction. While benzyl carbanions 4 can be trapped with carbon electrophiles, attempts at trapping aryl carbanions 5 with electrophiles other than H+ failed. In protic solvents, the magnesium salt of the tertiary alcohol 2 shows an increased rate of proximal cleavage as compared to its alkali salts. From this, we conclude that, in contrast to benzyl carbanions 4, free aryl carbanions 5 are of transient existence only. Proximal C,C-bond cleavage seems to occur either through protonation of 5 from a fast, reversible equilibrium 3?5 in which 3 strongly predominates, or in protic solvents possibly even through a rate-limiting protonation of 3 at the aromatic C-atom, bypassing free anion 5 altogether. Thus, additional factors other than just the relative stability of isomeric carbanions 4 and 5 are of importance in determining the regiochemistry of the base-induced C,C-bond cleavage in ketones 1 and in alcohols 2.