1,2-dimethylidenecyclopentane

Base Information

• Chemical Name: 1,2-dimethylidenecyclopentane
• CAS No.: 20968-70-1
• Molecular Formula: C7H10
• Molecular Weight: 94.1564
• Mol file: 20968-70-1.mol

Synonyms:

Chemical Property of 1,2-dimethylidenecyclopentane

Chemical Property:

• Vapor Pressure: 33.3mmHg at 25°C
• Boiling Point: 106.2°C at 760 mmHg
• Density: 0.81g/cm³

Purity/Quality:

Safty Information:

• Pictogram(s):  
• Hazard Codes: 

MSDS Files:

SDS file from LookChem

Useful:

Technology Process of 1,2-dimethylidenecyclopentane

There total 29 articles about 1,2-dimethylidenecyclopentane which guide to synthetic route it. The literature collected by LookChem mainly comes from the sharing of users and the free literature resources found by Internet computing technology. We keep the original model of the professional version of literature to make it easier and faster for users to retrieve and use. At the same time, we analyze and calculate the most feasible synthesis route with the highest yield for your reference as below:

synthetic route:

Reference yield: 81.0%

trans-1,2-Bis(bromomethyl)cyclopentane (100911-00-0,121887-60-3,121887-61-4) → 1,2-dimethylenecyclopentane (20968-70-1)

Guidance literature:

With potassium hydroxide; calcium oxide; at 150 ℃; for 3h; under 100 Torr;

DOI:10.1002/hlca.19940770714

Reference yield:

spiro<3.3>heptane-1-one (63049-05-8) → cyclobutylidenecyclopropane (16764-72-0) + Bicyclo<3.2.0>hept-1(5)-en (10563-10-7) + 1,2-dimethylenecyclopentane (20968-70-1) + 1-methylenespiro[2.3]hexane (20036-34-4)

Guidance literature:

Multi-step reaction with 3 steps

1: ethanol / Heating

2: sodium hydride / tetrahydrofuran; pentane / 6 h

3: 250 °C / 0 Torr / Pyrolysis

With sodium hydride; In tetrahydrofuran; ethanol; pentane;

DOI:10.1021/acs.joc.6b02445

Reference yield:

spiro[3.3]heptan-1-one p-tosylhydrazone → cyclobutylidenecyclopropane (16764-72-0) + Bicyclo<3.2.0>hept-1(5)-en (10563-10-7) + 1,2-dimethylenecyclopentane (20968-70-1) + 1-methylenespiro[2.3]hexane (20036-34-4)

Guidance literature:

Multi-step reaction with 2 steps

1: sodium hydride / tetrahydrofuran; pentane / 6 h

2: 250 °C / 0 Torr / Pyrolysis

With sodium hydride; In tetrahydrofuran; pentane;

DOI:10.1021/acs.joc.6b02445

upstream raw materials:

1,2-bis((dimethylamino)methyl)cyclopentane

2-<(Dimethylamino)methyl>1,1-methylenecyclopentane

trans-1,2-Bis(acetoxymethyl)cyclopentane

5-Methylenespiro<3.4>octane

Downstream raw materials:

3-Phenyl-1,3,4,5,6,7-hexahydro-cyclopenta[d][1,2]oxazine

3,4-Diphenyl-3,4,5,6,7,8-hexahydro-1H-cyclopenta[e][1,2]oxazepine

(R)-6-Methylene-2,3-diphenyl-1-oxa-2-aza-spiro[4.4]nonane

(S)-6-Methylene-2,3-diphenyl-1-oxa-2-aza-spiro[4.4]nonane

Refernces

• 1、 Bailey,Sorenson. "-". . p. 5421. Retrieved 1954.
• 2、 Rosenberg, Murray G.,Schrievers, Theodor,Brinker, Udo H.. "Competitive 1,2-C Atom Shifts in the Strained Carbene Spiro[3.3]hept-1-ylidene Explained by Distinct Ring-Puckered Conformers". . p. 12388 - 12400. Retrieved 2016/12/23.
• 3、 Monnat, Frederic,Vogel, Pierre,Sordo, Jose Angel. "Hetero-Diels-Alder and cheletropic additions of sulfur dioxide to 1,2-dimethylidenecycloalkanes. Determination of thermochemical and kinetics parameters for reactions in solution and comparison with estimates from quantum calculations". . p. 712 - 732. Retrieved 2007/10/03.