Synthesis 2001(15): 2289-2298
DOI: 10.1055/s-2001-18446
PAPER
© Georg Thieme Verlag Stuttgart · New York

1,2-Branched 1st to 4th Generation Carbosiloxane Dendrimers with a Me2SiO2 or MeSiO3 Core

Roy Buschbeck, Karin Brüning, Heinrich Lang*
Technische Universität Chemnitz, Fakultät für Naturwissenschaften, Institut für Chemie, Lehrstuhl Anorganische Chemie, Straße der Nationen 62, 09111 Chemnitz, Germany
e-Mail: heinrich.lang@chemie.tu-chemnitz.de;
Further Information

Publication History

Received 17 July 2001
Publication Date:
05 August 2004 (online)

Abstract

A straightforward method for the preparation of 1 → 2-branched carbosiloxane dendrimers of the 1st to 4th generation with a Me2SiO2 or a MeSiO3 core by applying repetitive hydrosilylation-alcoholysis cycles is described. All dendrimers prepared contain as repeated units SiOCH2CH2CH2 entities and feature SiMe2Cl, SiMeCl2 or Si(OCH2CH=CH2) end-grafted moieties. Depending on the different initiator cores MeSi(OCH2CH=CH2)3 (MeSiO3) (17) and Me2Si(OCH2CH=CH2)2 (Me2SiO2) (1), 1,2-branched carbosiloxane dendrimers up to the 3rd (17) or 4th (1) generation are accessible. However, further hydrosilylation of the latter molecules only results in the formation of irregular structured species, due to increasing steric congestions on the respective dendrimer surface. The formation of analytically pure and uniform carbosiloxane dendritic molecules is based on elemental analyses, IR, 1H, 13C{1H} and 29Si{1H} NMR spectroscopic studies. From selected examples gel permeation chromatography was carried out.

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Lang, H.; Lühmann, B. Adv. Mater. 2001, in print, and literature cited therein.