University of Maryland DRUM  
University of Maryland Digital Repository at the University of Maryland

DRUM >
Theses and Dissertations from UMD >
UMD Theses and Dissertations >

Please use this identifier to cite or link to this item: http://hdl.handle.net/1903/12771

Title: Synthesis of Functionalized Diazoacetoacetates via Mukaiyama-type Condensations
Authors: Liu, Yu
Advisors: Doyle, Michael P
Department/Program: Chemistry
Type: Dissertation
Sponsors: Digital Repository at the University of Maryland
University of Maryland (College Park, Md.)
Subjects: Chemistry
Keywords: 3-alkoxycyclobutanone
diazoacetoacetates
dirhodium catalyst
Mukaiyama-Michael
resorcinol
Issue Date: 2011
Abstract: Mukaiyama-type condensation reactions of 3-<italic>tert</italic>-butyldimethylsiloxy-2-diazo-3-butenoate and different electrophiles are effective methods for the synthesis of highly substituted diazoacetoacetates. With 0.5-3 mol% of Zn(OTf)<sub>2</sub> as Lewis acid catalyst, Mukaiyama-Michael reactions of vinyldiazoacetates and &alpha,&beta-unsaturated ketones proceed at ambient temperature to afford functionalized diazoacetoacetates in good yields. By carefully choosing the reaction conditions, both Mukaiyama-Michael adducts in either silyl enol ether form or in ketone form can be synthesized. Addition products obtained from these Mukaiyama-Michael reactions are investigated in dirhodium(II) catalyst induced dinitrogen extrusion reactions. Enedione-diazoester derived from Mukaiyama-Michael reaction of 3-<italic>tert</italic>-butyldimethylsiloxy-2-diazo-3-butenoate and 4-methoxy-3-bute-2-one can be converted to resorcinol derivatives under base catalysis. This novel transformation was investigated and developed into a synthetic methodology for the preparation of poly-substituted resorcinol compounds. Orthoesters also react with 3-<italic>tert</italic>-butyldimethylsiloxy-2-diazo-3-butenoate in the presence of Lewis acid catalysts. Diazoacetoacetates that contain acetal functionality can be assembled by these reactions. Rhodium(II) acetate promoted dinitrogen extrusion reactions of these adducts can give &beta-alkoxycyclbutanone products, which are useful synthons in organic synthesis.
URI: http://hdl.handle.net/1903/12771
Appears in Collections:UMD Theses and Dissertations
Chemistry & Biochemistry Theses and Dissertations

Files in This Item:

File Description SizeFormatNo. of Downloads
Liu_umd_0117E_12895.pdf6.28 MBAdobe PDF159View/Open

All items in DRUM are protected by copyright, with all rights reserved.

 

DRUM is brought to you by the University of Maryland Libraries
University of Maryland, College Park, MD 20742-7011 (301)314-1328.
Please send us your comments. -
All Contents