5-chloro-1-pentene - 5-cloro-1-penteno

IUPAC name
Other names 4-pentenyl
chloride 1-chloro-4-pentene
Semi-developed formula Cl CH 2 - (CH 2 ) 2 -CH = CH 2
Molecular formula C 5 H 9 Cl
CAS number 928-50-7[1]
ChemSpider 456250
PubChem 523042
Physical properties
Appearance Liquid
Density 889 kg/; 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
Chemical properties
Solubility in water 370 mg / L
log P 2,53
Family Haloalkene
Flash point 280 K (7 °C)
Related compounds
chloroalkenes 6-cloro-1-hexeno
cloroalcanos 1-chloropentane
chloroalkanes 5-chloro-1-pententine
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 . [3][5]


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 ]

See also

The following compounds are isomers of 5-chloro-1-pentene: