5-chloro-1-pentene - 5-cloro-1-penteno
|Semi-developed formula||Cl CH 2 - (CH 2 ) 2 -CH = CH 2|
|Molecular formula||C 5 H 9 Cl|
|Density||889 kg/m³; 0,889 g/cm³|
|Molar mass||104.58 g / mol|
|Melting point||−74 °C (199 K)|
|Boiling point||102 °C (375 K)|
|Vapor pressure||39,9 mmHg|
|Refractive index (n D )||1,4275|
|Solubility in water||370 mg / L|
|Flash point||280 K (7 °C)|
|chloroalkenes|| 6-cloro-1-hexeno |
|Values in the SI and under standard conditions|
(25 ℃ and 1 atm ), unless otherwise indicated.
The 5-chloro-1-pentene , also called 5-chloropent-1-ene or chloride 4-pentenyl , is an organic compound of molecular formula C 5 H 9 Cl . It is a haloalkane linear five carbon with an atom of chlorine bonded to one of the terminal carbons and one double bond at the opposite end of the carbon chain . [ 2 ] [ 3 ] [ 4 ]
Physical and chemical properties
At room temperature , 5-chloro-1-pentene is a liquid with a density lower than that of water, ρ = 0.889 g / cm³ . It has its boiling point at 102 ° C and its melting point at -74 ° C, the latter being an estimated value. The value of the logarithm of the partition coefficient , log P = 2.53, it indicates that it is soluble in solvents apolar to polar solvents. Its solubility in water is about 370 mg / L . 
5-Chloro-1-pentene can be synthesized by treating a solution of 4-penten-1-ol in ether and pyridine with thionyl chloride . The reaction is kept at 75 ° C for an hour and a half. [ 6 ] This compound can also be prepared from 1,1-dibromo-5-chloropentane and butyllithium in diethyl ether at -30 ° C temperature. In this case the yield is 75%. [ 7 ]
Another synthesis method consists of the hydroalumination of 5-chloro-1-pentyne with diisobutylaluminum hydride, a reaction catalyzed by nickel , which leads to the formation of the corresponding α-vinyl aluminum isomers . Its subsequent treatment with chlorine allows to obtain 5-chloro-1-pentene. [ 8 ]
5-Chloro-1-pentene is a precursor to compounds such as 5-chloro-1-iodopentane . [ 6 ] It can also be disproportionate —reaction in which an olefin is transformed into other olefins of different molecular weights— into ethylene , and cis- and trans - 1,8-dichloro-4-octene . For this, a catalytic system is used that comprises a metal from groups IVa, IVb, Vb, VIb, VIIb, VIII and Ib of the periodic table and at least one neutral carbene complex , that is, non-ionic. [ 9 ]
Treatment of 5-chloro-1-pentene with borane / tetrahydrofuran at 0 ° C provides an organoboron compound , the oxidation of which with N -trimethylamine oxide in diglyme allows to obtain 5-chloropentanol . The yield of this procedure is 95%. [ 10 ] Similarly, in the presence of air and water, trialkylborans generated in situ from borane and 5-chloro-1-pentene, can be added to benzo-1,4-quinone to give benzene-1,4-diols 2 -replaced. [ 11 ]
The following compounds are isomers of 5-chloro-1-pentene:
- CAS number
- 5-Chloro-1-pentene (PubChem)
- 5-Chloro-1-pentene (ChemSpider)
- 5-Chloro-1-pentene (Chemical Book)
- 5-chloropent-1-ene. Safety data sheet (Echemi.com)
- Radiohalogenation method (1981) Kabalka, GW Patent US4450149A
- Kostikov, R.R.; Khlebnikov, A.F.; Sokolov, V.V. (2010). «188.8.131.52.1 Variation 1: Dehalogenation of Geminal Dihalides». Science of Synthesis 47: 840. Consultado el 28 de enero de 2020.
- Gao, F.; Hoveyda, A.H. (2010). «α-Selective Ni-Catalyzed Hydroalumination of Aryl- and Alkyl-Substituted Terminal Alkynes: Practical Syntheses of Internal Vinyl Aluminums, Halides, or Boronates». J. Am. Chem. Soc. 132 (32): 10961-10963. Consultado el 28 de enero de 2020.
- Olefin disproportionation (1979) Banasiak, DS Patente US4269780A
- Ishihara, K.; Yamamoto, H. (2005). «184.108.40.206.2 Variation 2: Oxidation of Alkylboranes with Amine N-Oxides». Science of Synthesis 6: 409. Consultado el 28 de enero de 2020.
- Marsini, M.A.; Pettus, T.R.R. (2007). «220.127.116.11.2.1 Variation 1: 1,4-Addition of Trialkylboranes». Science of Synthesis 31: 424. Consultado el 28 de enero de 2020.