Synthesis and Structure of 1,5-Di-(Ethylphenyl)-1,5-Dimethyl-3,3,7,7-Tetraphenylcycloterasiloxane: a Novel Cyclotetramer

Herein we report the first synthesis of 1,5- di-(ethylphenyl)-1,5-dimethyl-3,3,7,7-tetraphenylcyclotetrasiloxane using a new ‘One Pot’ procedure as recently reported for the preparation of strictly alternating 1,1,5,5-tetramethyl-3,3,7,7-tetraphenylcyclotetrasiloxane by the heterofunctional condensation of diphenylsilanediol with (phenylethyl)methyldichlorosilane in the presence of the ter tiary amine, triethylamine (Nguyen et al. Silicon 6:21–26 2014). The prepared 1,5-di-(ethylphenyl)-1,5-dimethyl-3,3,7,7-tetraphenylcyclotetrasi loxane was fully characterized by single-crystal X-ray diffraction, ¹H, ¹³C and ²⁹Si nuclear magnetic resonance spectroscopy, elemental analysis, mass spectroscopy, thermogravimetric analysis and differential scanning calori metric studies.