Asymmetrische Synthese von bicyclischen Alpha-Aminosäuren durch intramolekulare Pauson-Khand-Reaktion von l-Alkenylsulfoximinen und Festphasensynthese mit Allylsulfoximinen

Described is an asymmetric synthesis of novel bicyclic alpha-amino acids having a hexahydro cyclopenta[c]pyridine skeleton, carrying an enone structural element, and a substituent in beta-position. Starting from enantiomerically pure (S)-N,S-Dimethyl-S-phenylsulfoximine allylic sulfoximines could easily be prepared in 55-70% yield following a well established addition elimination isomerization route. A regio and diastereoselective allylation of N-tert-Butysulfonyliminoester with titanated allylic sulfoximines led to gamma,delta-unsaturated alpha-amino acid esters (de < 98%) in 67-85% yield. Propargylation at the amino nitrogen atom gave 5-Azaoct-1-en-7-ynes in 91-95% yield. Pauson-Khand Reaction of these Enynes with Co2(CO)8 activated by N-Morpholine-N-oxide (NMO) afforded hexahydrocyclopenta[c]pyridine carboxylic acids with high selectivity (dr up to 98:2) and moderate yields (49-60%). The sulfoximine moiety was cleaved during the reaction under inversion at the sulfur atom forming enantiomerically pure sulfinamide. The deprotection of the sulfonylamino group could be shown in one example with 85% yield. In a second part of this thesis the synthesis of polymer-bound allylic sulfoximines and their use in the asymmetric synthesis of alkenyl oxiranes is described. The allylsulfoximine resins were converted to homoallylic alcohols via alpha-hydroxyalkylation. Cleavage from the polymer was performed via substitution of the sulfoximine moiety by a chlorine atom. The obtained mixture of syn- and anti- chlorohydrins (ee < 70%) could be converted to the corresponding mixture of cis- and trans-alkenyloxiranes.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2004

Author dc:creator

• Günter, Markus

Contributors dc:contributor

• Gais, Hans-Joachim

• info:eu-repo/classification/ddc/540
• Aminosäuren
• Bicyclische Verbindungen
• Asymmetrische Synthese
• Alkenylsulfoximide
• Pauson-Khand-Reaktion
• Intramolekulare Reaktion
• Festphasentechnik
• Chemie
• bicyclische alpha- Aminosäuren
• Pauson-Khand Reaktion
• Festphasensynthese
• Sulfoximine

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123594%22

OAI identifier oai:identifier

oai:publications.rwth-aachen.de:61993