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Identifier

000378704

Title

Οξειδωτική κυκλοπροσθήκη 1, n-διυδρο ολιγοσιλανίων σε αλκύνια καταλυόμενη από νανοσωματίδια Au

Alternative Title

Dehydrogenative cycloaddition of tethered 1, n-dihydrodisilanes to alkynes catalyzed by gold nanoparticles

Author

Κοτζαμπασάκη, Βασιλική Στ

Thesis advisor

Στρατάκης, Εμμανουήλ

Reviewer

Βασιλικογιαννάκης, Γεώργιος
Σμόνου, Ιουλία

Abstract

In the current Thesis a generalized methodology of the dehydrogenative addition of 1,n-dihydro-tethered oligosilanes to alkynes is presented. Furthermore, mechanistic studies regarding the reaction among 1,1,3,3 tetramethyldisiloxane and alkynes were carried out. In addition, we present the synthetic use of 2,5-dihydro-1,2,5-oxadisiloles, products of these reactions, in C-C coupling reactions with aryl iodides catalyzed by Pd(II), the known Hiyama coupling. The results can be summarized as follows: · Au/TiO₂ catalyzes the dehydrogenative addition of 1,1,3,3- tetraphenyldisiloxane, 1,1,1,3,5,7,7,7-octamethyltetrasiloxane, 1,1,3,3,5,5- hexamethyltrisiloxane and 1,2-bis(dimethylsilyl)benzene to alkynes in high yields. · The formation of the seven-membered heterocyclic ring of 4,7-dihydro- 1,3,2,4,7 dioxatrisilepines by the Au-catalyzed reaction among alkynes and 1,1,3,3,5,5-hexamethyltrisiloxane appears for first time in literature. · The mechanism of the dehydrogenative addition of 1,1,3,3- tetramethyldisiloxane to alkynes is postulated, which includes a formal [3+2] cycloaddition via a cyclo-gold-disiloxane intermediate. · The Hiyama coupling (Pd(II), aryl iodides) of 2,5-dihydro-1,2,5-oxadisiloles was studied and found to form products of mono or di-substitution depending on the steric hindrance of the tertiary olefinic carbon atom of the reacting oxadisilole.

Language

Greek

Subject

1,n-διυδρο ολιγοσιλάνια

2,5-dihydro-1,2,5-oxadisiloles

2,5-διυδρο-1,2,5-οξαδισιλόλια

Heterogeneous catalysis

Hiyama coupling

ετερογενής κατάλυση

σύζευξη Hiyama

Issue date

2013-02-26