The Benzene,(ethenylmethylsilyl)-, with the CAS registry number 17878-39-6 and EINECS registry number 241-830-5, has the systematic name of ethenyl(methyl)phenylsilane. It is a kind of clear colorless liquid, and the molecular formula of the chemical is C₉H₁₂Si.

The characteristics of Benzene,(ethenylmethylsilyl)- are as followings: (1)ACD/LogP: 4.10; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 5.5): 4.1; (4)ACD/LogD (pH 7.4): 4.1; (5)ACD/BCF (pH 5.5): 771.43; (6)ACD/BCF (pH 7.4): 771.43; (7)ACD/KOC (pH 5.5): 4058.16; (8)ACD/KOC (pH 7.4): 4058.16; (9)#H bond acceptors: 0; (10)#H bond donors: 0; (11)#Freely Rotating Bonds: 2; (12)Polar Surface Area: 0 Å²; (13)Flash Point: 40.7 °C; (14)Enthalpy of Vaporization: 39.1 kJ/mol; (15)Boiling Point: 171.4 °C at 760 mmHg; (16)Vapour Pressure: 1.87 mmHg at 25°C. 

Preparation of Benzene,(ethenylmethylsilyl)-: This chemical can be prepared by chloro-methyl-phenyl-vinyl-silane. The reaction will need reagent LiAlH₄, and the yield is about 84%. 

You should be cautious while dealing with this chemical. It irritates to eyes, respiratory system and skin. Therefore, you had better take the following instructions: Wear suitable gloves and eye/face protection, and if in case of contacting with eyes, rinse immediately with plenty of water and seek medical advice. 

Addtionally, the following datas could be converted into the molecular structure:
(1)SMILES: C(=C)\[SiH](c1ccccc1)C
(2)InChI: InChI=1/C9H12Si/c1-3-10(2)9-7-5-4-6-8-9/h3-8,10H,1H2,2H3
(3)InChIKey: JNRFDZNGKYQSKV-UHFFFAOYAB