Application of the intramolecular PIFA-mediated amidation of alkynes to the synthesis of substituted indolizidinones
摘要:
The construction of the title compounds has been achieved from properly substituted linear alkynylamides through the suitable combination of two key cyclization steps. First, an intramolecular PIFA-mediated alkyne amidation protocol leads to the creation of the pyrrolidinone nucleus, which under proper manipulation of the generated keto carbonyl group permits the assembling of the indolizidinone skeleton by the introduction of a subsequent ring closing olefin metathesis step. Finally, its transformation into a series of substituted mono- and trihydroxylated indolizidinone derivatives is achieved by manipulation of the remaining unsaturated fragment under hydrogenation and dihydroxylation conditions. (C) 2012 Elsevier Ltd. All rights reserved.
A novel domino reaction, alkyne-mediated domino hydroformylation/double cyclization, has been developed for rapid preparation of indolizidine type alkaloids. DFT calculations were applied for rationales of reactivity and selectivity. A concise synthesis of tashiromine as the application of the methodology is also reported.
Rhodium-Catalyzed Domino Hydroformylation/Double-Cyclization Reaction of Arylacetylenecarboxamides: Diastereoselectivity Studies and Application in the Synthesis of 1-Azabicyclo[<i>x.y</i>
.0]alkanes
A domino method for the rapid syntheses of 1‐azabicyclo[x.y.0]alkane scaffolds, such as indolizidines, quinolizidines, decahydropyridoazepines, and their derivatives, has been developed. This strategy involved a rhodium‐catalyzed hydroformylation of allyl‐, 3‐butenyl‐, or homoallyl amides, followed by two spontaneous ring closures under mild conditions. The reaction scope and diastereoselectivity were
The Combination of Relay and Cooperative Catalysis with a Gold/Palladium/Brønsted Acid Ternary System for the Cascade Hydroamination/Allylic Alkylation Reaction
作者:Hua Wu、Yu-Ping He、Liu-Zhu Gong
DOI:10.1002/adsc.201100922
日期:2012.4.16
The combination of relay and cooperative catalysis with a gold/palladium/Brønstedacid ternary system renders a cascade hydroamination/allylic alkylation reaction to provide an unprecedented entry to pyrrolidinederivatives in high yields.