The Hexamethylcyclotrisiloxane , with cas registry number of 541-05-9, belongs to the categories of (1) Siloxanes ; (2) Organics ; (3) Si (Classes of Silicon Compounds) ; (4) Si-O Compounds ; (5) Organometallic Reagents ; (6) Organosilicon. Its IUPAC name is 2,2,4,4,6,6-hexamethyl-1,3,5,2,4,6-trioxatrisilinane . And its systematic name is 2,2,4,4,6,6-hexamethyl-1,3,5,2,4,6-trioxatrisilinane . This compound is stable, but moisture sensitive. It is also incompatible with strong oxidizing agents.

Physical properties of Hexamethylcyclotrisiloxane are: (1) #H bond acceptors: 3 ; (2) #H bond donors: 0 ; (3) #Freely Rotating Bonds: 0 ; (4) Index of Refraction: 1.417 ; (5) Molar Refractivity: 59.26 cm³ ; (6) Molar Volume: 235.4 cm³ ; (7) Surface Tension: 17.5 dyne/cm ; (8) Enthalpy of Vaporization: 35.34 kJ/mol ; (9) Vapour Pressure: 11.6 mmHg at 25°C.

Preparation of Hexamethylcyclotrisiloxane : This chemical can be prepared by many ways. Here will give a example, use octamethyl-cyclotetrasiloxane as reactants. And the reaction occures under the temperature of 140 - 170 ℃ for 5 hours using the reagent of Aluminium iodide . The yield is 99%.

Uses of Hexamethylcyclotrisiloxane : (1) Hexamethylcyclotrisiloxane is used to the manufacture of methyl vinyl silicone rubber products, and is also an important raw material synthesis of other polymers. In addition to the general synthesis of silicone polymers, it can also be used to prepare a specific organic silicon compounds, as a variety of surface treatment agent, coupling agent, crosslinking agent, etc. (2) Hexamethylcyclotrisiloxane is used to prepare many other chemicals. For example, it reacts with tert-butyl-lithium in the solvent of diethyl ether and other conditions: 1.) 0 deg C, 1 h, 2.) To 25 deg C, 1.5 h. The yield is about 98%.

When you are using this chemical, please be cautious about it as the following:
The Hexamethylcyclotrisiloxane is highly flammable and irritating to eyes, respiratory system and skin. If contact with eyes accidently, rinse immediately with plenty of water and seek medical advice. It should be stored in flammables area.

You can still convert the following datas into molecular structure:
(1) SMILES:O1[Si](O[Si](O[Si]1(C)C)(C)C)(C)C;
(2) InChI:InChI=1/C6H18O3Si3/c1-10(2)7-11(3,4)9-12(5,6)8-10/h1-6H3;
(3) InChIKey:HTDJPCNNEPUOOQ-UHFFFAOYAR