Telomerization of cyclodimethylsiloxanes

Summary

• 1. The reaction of hexamethylcyclotrisiloxane with organotrichlorosilanes in absence of catalysts results in the formation of telomers of formula

  $$\mathop {RSi - }\limits_{\mathop {Cl}\limits^| }^{\mathop {Cl}\limits_| } \left( {\mathop {OSi - }\limits_{\mathop {CH_3 }\limits^| }^{\mathop {CH_3 }\limits_| } } \right)_{3n} Cl$$

• 2. In presence of catalytic amounts of ferric chloride, oligomers of formula$\mathop {RSi - }\limits_{\mathop {Cl}\limits^| }^{\mathop {Cl}\limits_| } \left( {\mathop {OSi - }\limits_{\mathop {CH_3 }\limits^| }^{\mathop {CH_3 }\limits_| } } \right)_n Cl$ may be formed, or change may occur in the functionality of the oligomers.

• 3. The activity of the organotrichlorosilane in these reactions depends on the nature of the silicon-attached group and falls along the series: CH₃ > C₂H₅ > CH₂=CH > C₆H₅.

• 4. Twenty previously undescribed compounds were isolated and characterized.