4125-18-2

Basic information

• Product Name: 1,3-Cyclopentadiene, 5,5-dimethyl-
• Synonyms: 1,3-Cyclopentadiene, 5,5-dimethyl-;1,1-Dimethyl-2,4-cyclopentadiene;5,5-Dimethyl-1,3-cyclopentadiene
• CAS NO: 4125-18-2
• Molecular Formula: C₇H₁₀
• Molecular Weight: 94.15
• Mol File: 4125-18-2.mol
• Article Data: 3

Chemical Properties

• Boiling Point: 92.9°C at 760 mmHg
• Appearance: /
• Density: 0.827g/cm³
• Vapor Pressure: 57.5mmHg at 25°C
• Refractive Index: 1.467
• CAS DataBase Reference: 1,3-Cyclopentadiene, 5,5-dimethyl-(CAS DataBase Reference)
• NIST Chemistry Reference: 1,3-Cyclopentadiene, 5,5-dimethyl-(4125-18-2)
• EPA Substance Registry System: 1,3-Cyclopentadiene, 5,5-dimethyl-(4125-18-2)

Safety Data

• Hazardous Substances Data: 4125-18-2(Hazardous Substances Data)

Usage

Synthesis Reference(s)

Tetrahedron Letters, 17, p. 2225, 1976 DOI: 10.1016/0040-4039(76)80034-2

InChI:InChI=1/C7H10/c1-7(2)5-3-4-6-7/h3-6H,1-2H3

Upstream product

• 1638-26-2 1,1-Dimethylcyclopentane 
• 22748-16-9 4,4-dimethylcyclopent-2-ene-1-one 

Downstream Products

• 1638-26-2 1,1-Dimethylcyclopentane 
• 71805-64-6 5,5-dimethylbicyclo<2.1.0>pentane 
• 85407-29-0 4,4-dimethyl-7,7-diphenylbicyclo<3.2.0>hept-2-en-6-one 
• 90424-89-8 2-benzoyl-5,6,7,7-tetramethylbicyclo<2.2.1>hepta-2,5-diene 
• 74503-34-7 5,5-Dimethylbicyclo<2.1.0>pent-2-ene 
• 318240-05-0 5,5-dimethyl-3,4-epoxy-1-cyclopentene 
• 94986-29-5 Ir((FC₆H₄)3P)2((CH₃)2C₅H₄)⁽¹⁺⁾*SbF₆^(1-)=(Ir((FC₆H₄)3P)2((CH₃)2C₅H₄))SbF₆ 

Relevant articles and documents

Mechanism of the Cyclopropane "Walk" Rearrangement: Syntheses and Properties of Diazoalkane Adducts of 1,3-Cyclobutadiene

The synthesis and the thermal and photochemical behaviour of the specifically deuterated 2-diazopropane- and 2-diazo-1-methoxypropane adducts of 1,3-cyclobutadiene -1a, -1b, and -1c are reported.The elimination of N2 in -1a photochemically as well as thermally induced leads to a 1:1 mixture of the regioisomeric bicyclopentenes -3a and -3a or cyclopentadienes -12a and -12a formed as secondary products.Photolysis of the diastereomeric adducts -1b and -1c reveals that after extrusion of N2 each ring closure reaction between C-5 and C-1 or C-5 and C-3 gives the corresponding bicyclopentene system stereospecifically with retention at C-5.Diradicals -2b and -2c are postulated to be the transition states of the cyclisation reactions.The observation that the "walk" rearrangement in the bicyclopentene system proceeds with inversion at C-5 rules out the participation of a diradical of type 2 in this process.

REACTIONS OF ALKANES AND CYCLOALKANES ON PLATINUM-GOLD ALLOY FILMS

The reactions of a series of cyclic and acyclic alkanes in excess hydrogen have been studied on evaporated films of Pt-Au.Film homogeneity was established by X-ray fluorescence spectroscopy and X-ray diffraction.The reactions which occur fall into two groups.First there are those whose rate is dramatically affected by Au incorporation in Pt, and these include the hydrogenolysis of ethane, neopentane, n-pentane, neohexane and n-hexane, the isomerization of neopentane and n-pentane and finally the ring opening and hydrocracking of the cyclopentane ring.Secondly, there are reactions whose rate is essentially unaffected by moderate Au incorporation in Pt, comprising the 1,5-cyclization of n-pentane, the 1,6-cyclization of n-hexane, the ring enlargement of methylcyclopentane and of 1,1-dimethylcyclopentane and finally dehyrogenation of saturated hydrocarbons to alkene and alkadiene.These results may be rationalized on either an electronic factor or by postulating that gold atoms locate preferentially at rough regions of the surface.