Hexachlorocyclopentadiene, also known as C-56, is an organochlorine compound that is a precursor to several pesticides. This colourless liquid is an inexpensive reactive diene. Many of its derivatives proved to be highly controversial, as studies showed them to be persistent organic pollutants. Collectively, the pesticides derived from hexachlorocyclopentadiene are called the cyclodienes. An estimated 270,000 tons were produced until 1976, and some are still manufactured by Velsicol Chemical Corporation in the US and by Jiangsu Anpon Electrochemicals Co. in China.

CAS：77-47-4
中文别名：六氯戊二烯;1,2,3,4,5,5-六氯环戊-1,3-二烯;六氯-1,3-环戊二烯;
英文别名：1,3-Cyclopentadiene, 1,2,3,4,5,5-hexachloro-;1,2,3,4,5,5-hexachlorocyclopenta-1,3-diene;
分子式：C5Cl6
分子量：272.772
精确质量：269.813
Psa：0.0
Logp：4.5523

MDL号：MFCD00001352

外观与性状：透明至淡黄色液体
密度：1.702g/mLat 25°C(lit.)
沸点：239°C753mm Hg(lit.)
熔点：−10°C(lit.)
闪点：109°C
折射率：n20/D 1.5644(lit.)
稳定性：Stability Stable, but light-sensitive. Non-flammable. Very reactive with alkenes and polynuclear hydrocarbons. Explosive with sodium. Incompatible with strong oxidizing agents, most common metals.
储存条件：库房通风低温干燥,与氧化剂,食品分开储运
蒸汽压：0.13 psi ( 20 °C)

RTECS号：GY1225000
安全说明：S23-S39-S45-S61-S60-S53-S25-S36/37-S16
WGK Germany：3
危险类别码：R22; R24; R26; R34; R50/53
危险品运输编码：UN 2646 6.1/PG 1
海关编码：2903890090
危险类别：6.1(a)
包装等级：I
危险品标志：T+; N