Dehydrogenations with lead tetraacetate. Ketone to enone transformations in the 2-(aminocarbonyl)- and 2-(carbalkoxy)cycloalkanone series

Tandem Oxidation/Rearrangement of β-Ketoesters to Tartronic Esters with Molecular Oxygen Catalyzed by Calcium Iodide under Visible Light Irradiation with Fluorescent Lamp

“…In particular, tartronic esters and hydroxymalonic esters have been studied as biodegradable organic builders for surfactants . The prevalent way for the preparation of tartronic esters is the oxidation of the corresponding malonic esters with heavy metal oxidants (i.e., Pd(OAc) 4 , MoOPH), peracids, or molecular oxygen catalyzed by various metal catalysts (i.e., Mn, Co, Cs, Ce, Pd) . However, some problems relating to these reactions, such as low yield, the necessity of stoichiometric amounts, or environmental high impact catalyst, deserve rectification.…”

Novel Manganese-Catalyzed α-Oxidation of Cyclic β-Keto Esters with Molecular Oxygen

“…The α-position of β-dicarbonyl compounds is naturally nucleophilic, and a number of electrophilic reagents can be utilized for introduction of an oxygen functionality at this position. Common examples are Pb(OAc) 4 , MOPH, percarboxylic acids, dimethyldioxirane, or singlet oxygen . In the course of our search for a chiral transition-metal catalyst for asymmetric Michael reactions, we discovered that Mn(OAc) 2 ·4H 2 O does catalyze the oxidation of ester 1a , if air was not excluded.…”

Synthesis and bioactivity of analogues of the marine antibiotic tropodithietic acid

“…Finally, a few cycloheptanone derivatives with rigorously simplified structures as compared to TDA were included in this study. The β-ketoester 27 containing a Michael acceptor was synthesised from methyl cycloheptanone-2-carboxylate ( 26 ) by oxidation with Cu(OAc) 2 and Pb(OAc) 2 according to a known procedure [ 16 ]. The compound cyclohept-2-en-1-one ( 28 ) is commercially available, while we have previously reported the synthesis of cyclohept-4-en-1-one ( 29 ) that was identified in headspace extracts from streptomycetes [ 17 ].…”