ISSN:
1573-9171
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Conclusions 1. A method is developed for the preparation of two new cyclocarbasiloxanes: 2,2,4,4,6,6-hexameth-yl-1,3-dioxa-2,4,6-trisilaeyclohexane and 2,2,4,4,6,6,8,8-octamethyl-1,3,5-trioxa-2,4,6,8-tetrasilaeyclooctane. 2. In the heterofunctional condensation reaction between 2,4-dichloro-2,4-dimethyl-2,4-disilapentane and dipotassium dimethylsilanediolate, as well as the desired product 2,2,4,4,6,6-hexamethyl-1,3-dioxa-2,4,6-trisilacyclohexane (I), hexamethylcyclotrisiloxane, 2,2,4,4,6,6,8,8-octamethyl-1,3,5-trioxa-2,4,6,8-tetrasilacyclooctane (III) and 2,2,4,4,6,6,8,8-octamethyl-1,5-dioxa-2,4,6,8-tetrasilacyclooctane (IV) are formed. 3. In the cohydrolysis reactions of 2,4-dichloro-2,4-dimethyl-2,4-disilapentane with dichlorodimethylsilane and with 1,3-dichloro-1,1,3,3-tetramethyldisiloxane the same products are formed, namely, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, (I), (III), and (IV). In the best conditions for the preparation of (I) the reactant ratio is 1∶1. In the best conditions for the preparation of (III) the molar reactant ratio is again 1∶1 and a strongly acid medium is used. 4. The compound (III) readily polymerizes in presence of alkaline catalysts with formation of a macromolecular substance.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01106276
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