90113-78-3Relevant academic research and scientific papers
Oxidative iodination of carbonyl compounds using ammonium iodide and oxone
Marri, Mahender Reddy,MacHarla, Arun Kumar,Peraka, Swamy,Nama, Narender
supporting information; experimental part, p. 6554 - 6559 (2012/01/02)
A simple, efficient, mild, and regioselective method for oxyiodination of carbonyl compounds has been reported by using NH4I as the source of iodine and Oxone as an oxidant. Various carbonyl compounds such as aralkyl ketones, aliphatic ketones (acyclic and cyclic), and β-keto esters proceeded to the respective α-monoiodinated products in moderate to excellent yields. Unsymmetrical aliphatic ketones reacted smoothly yielding a mixture of 1-iodo and 3-iodo ketones with the predominant formation of 1-iodoproduct.
Practical formal total synthesis of (rac)- and (S)-camptothecin
Peters, Rene,Althaus, Martin,Nagy, Anne-Laure
, p. 498 - 509 (2007/10/03)
A practical, efficient and scalable formal total synthesis of (rac)- and (S)-camptothecin is described, which proceeds via the known DE ring building blocks 19 and (S)-19, respectively. The racemic synthesis starts from diethyl oxalate and uses straightforward carbonyl chemistry in order to generate the pyridone ring system. 19 was formed in 8.4% overall yield over 9 linear steps avoiding any chromatographic purification. The asymmetric version of this approach encompassed a diastereoselective Grignard addition to the enantiomerically pure α-ketoester 30 in order to generate the (S)-configured quaternary stereocenter. The auxiliary could be recycled in high yield and was successfully reused multiple times. The final steps paralleled the racemic approach. (S)-19 was thus prepared in 9.4% overall yield (er = 95: 5) over 10 steps. The Royal Society of Chemistry 2006.
Preparation of acyloins by cerium-catalyzed, direct hydroxylation of β-dicarbonyl compounds with molecular oxygen
Christoffers, Jens,Werner, Thomas,Unger, Sven,Frey, Wolfgang
, p. 425 - 431 (2007/10/03)
We report the metal-catalyzed α-hydroxylation of a variety of cyclic and acyclic β-dicarbonyl compounds by molecular oxygen. The decisive advantage of this new method is the use of catalytic amounts of the nontoxic cerium salt CeCl3·7H2O in 2-propanol at ambient temperature. Most of the cyclic substrates 4a-4i give high yields of analytically pure products 5a-5i, and the workup procedure is simple filtration through silica gel. The oxidation of acyclic dicarbonyl compounds 4j-4p, however, is accompanied by side reactions and decomposition, reducing the yields of products 5j-5p significantly. A proposed mechanism is in agreement with experimental results, in particular the observed oxygen uptake. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
Synthesis of 2-Hydroxy-3-oxocarboxylic Esters From the Corresponding α,β-Unsaturated Esters by a Simple One-Step Procedure
Crout, D. H. G.,Rathbone, D. L.
, p. 40 - 42 (2007/10/02)
A convenient one-step synthesis of 2-alkyl-2-hydroxy-3-oxocarboxylic esters by potassium permanganate oxidation of the corresponding readily available α,β-unsaturated esters is described.Preparation of the latter by the phosphonate modification of the Wit
