1,1,1,3,3,3-Hexachloropropane is a compound of chlorine, hydrogen, and carbon, with chemical formula C3Cl6H2, specifically Cl3C−CH2−CCl3.

[1][2] Its boiling point is significantly higher than expected based on estimations from various molecular parameters.

[5][6][7] The original synthesis by Davis and Whaley obtained the compound by reacting 1,1,3,3-tetrachloropropane and/or 1,1,1,3-tetrachloropropane with chlorine at 80-100 °C, through 1,1,1,3,3-pentachloropropane as an intermediate step.

[3][11] The compound has been considered as an intermediate in the manufacture of 1,1,1,3,3,3-hexafluoropropane, through reaction with hydrogen fluoride.

[15][16][17][18] A 2001 study found that the compound had significant effects on rat fetuses when inhaled at 25 ppm.