Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.605607
Title: Asymmetric organocatalysis in flow
Author: Jin, X.
Awarding Body: University of Cambridge
Current Institution: University of Cambridge
Date of Award: 2010
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Abstract:
This thesis is divided into two sections. In Section I, the desymmetrisation of a meso-cyclic anhydride was described. However, the transformation requires extremely low temperatures (-55°C) and a long reaction time (96 h) in order to achieve high enantioselectivity, which is not feasible for transfer into a continuous flow system. Later on, the work turned to investigation of its application towards the synthesis of chiral cyclopentanes using new enabling technologies. In Section II, the enantioselective Michael addition of aldehydes to nitroethylene in flow was described. The process was successfully incorporated into a flow system (R2+ and R4 unit). Key to this organocatalytic process is the use of catalytic amounts of a diphenylprolinol silyl ether catalyst with acetic acid as co-catalyst. This is an efficient catalytic system that enables faster transformation (1-3 h) with high enantioselectivities (up to 98% ee). A study on a proposed enol mechanism for this catalytic process was also discussed. Both sections provide full experimental procedures as well as characterisation in support of the results described within this thesis.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.605607  DOI: Not available
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