Issue 8, 2005

A posteriori” modification of carbosilane dendrimers and dendrons: their activation in core and branch positions

Abstract

The introduction of phenyl groups at different points on carbosilane dendrimers allows their acidolytic conversion to highly reactive triflato groups which in turn are readily substituted by anionic nucleophiles. Core phenylated first–fourth generation dendrimers were synthesized from tri(allyl)phenylsilane by an alternating sequence of hydrosilylation and allylation steps. Similarly, carbosilane dendrimers containing phenyl-Si groups at the branching points and in the periphery were prepared from tetraallylsilane which was hydrosilylated with PhHSiCl2. Reaction of the phenylated dendrimers with triflic acid in toluene cleanly gave the silyl triflate derivatives, provided that the correct stoichiometry of the reagents was used. In the presence of a large excess of triflic acid the SiMe3-end groups are slowly converted to SiMe2(OTf)-units. The proof of concept was provided by the fixation of a {Ph2PCH2} group using the lithiated diphenylphosphinomethanide Ph2PCH2Li, obtained by cleavage of Ph3SnCH2PPh2 with PhLi, as well as a lithiated ether-alcohol functionalized triphos derivative to the core of a third generation carbosilane dendrimer.

Graphical abstract: “A posteriori” modification of carbosilane dendrimers and dendrons: their activation in core and branch positions

Article information

Article type
Paper
Submitted
31 Qun 2005
Accepted
03 Cig 2005
First published
15 Cig 2005

Dalton Trans., 2005, 1394-1402

A posteriori” modification of carbosilane dendrimers and dendrons: their activation in core and branch positions

A. Tuchbreiter, H. Werner and L. H. Gade, Dalton Trans., 2005, 1394 DOI: 10.1039/B501069A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements