Reaction Of β,γ-Unsaturated Carboxylic Acids With Thallium Triacetate (Tta): Lactonization<i>VS</i>Oxidative Decarboxylation
作者:Helena M. C. Ferraz、Mčnica V. A. Grazini、Luiz F. Silva、Luiz S. Longo
DOI:10.1080/00397919908086184
日期:1999.6
Abstract The reaction of six β,γ-unsaturated carboxylic acids with thalliumtriacetate (TTA) was studied. The nature of the products is highly sensitive to the substitution pattern of the substrates. Aliphatic acids gave mainly lactones, while those bearing an aromatic ring furnished only decarboxylation products.
Expeditious Construction of (+)-Mintlactone via Intramolecular Hetero-Pauson−Khand Reaction
作者:Peng Gao、Peng-Fei Xu、Hongbin Zhai
DOI:10.1021/jo900045k
日期:2009.3.20
(+)-Mintlactone, a bicyclic monoterpene natural product, has been efficiently assembled from (-)-citronellol in three steps. The synthesis features nitrous acid-induced formal isopropylidene "demethanation" and the molybdenum-mediated intramolecular hetero-Pauson-Khand reaction.
Synthesis of optically active α-methylene γ-butyrolactones and (+)-mintlactone
作者:Geoffrey T. Crisp、Adam G. Meyer
DOI:10.1016/0040-4020(95)00236-2
日期:1995.5
combination of baker's yeast reductions of β-keto carbonyls, vinyl triflate formation and a palladium-catalysed, intramolecular, carbonylative coupling affords optically active α-methylene γ-butyrolactones. The synthesis of the unnatural (+)-mintlactone using this methodology is also described.
strategy has been used to concisely and efficiently complete the synthesis of (+)-mintlactone and (–)-isomintlactone via SmI2-induced intramolecular radical cyclization, two rings and a stereocenter were constructed in one step. In the synthesis, the stereochemistry of the final natural product is set relative to the stereocenter of (–)-citronellol and favored coordination transition state of samarium
Regio- and stereoselective selenium dioxide allylic oxidation of (E)-dialkyl alkylidenesuccinates to (Z)-allylic alcohols: Synthesis of natural and unnatural butenolides
作者:Ramesh M. Patel、Vedavati G. Puranik、Narshinha P. Argade
DOI:10.1039/c1ob05709j
日期:——
allylic alcohol formation of dialkyl alkylidenesuccinates has been demonstrated to accomplish one-stepsyntheses of several essential butenolides and fused butenolidesvia an unusual E- to Z- carbon–carbon double bond isomerisation followed by the lactonization pathway. The observed regio- and stereoselective SeO2 allylic oxidation protocol has also been extended to the diastereoselective total synthesis