129201-92-9Relevant academic research and scientific papers
Synthesis of the core structure of the fungal metabolite benesudon: Use of oxidative decarboxylation
Clive, Derrick L. J.,Minaruzzaman,Yang, Haikang
, p. 5581 - 5583 (2005)
(Chemical Equation Presented) The core structure (5) of the fungal metabolite benesudon (1) was synthesized, the key step being oxidative decarboxylation of acid 17.
Late-Stage Intermolecular Allylic C-H Amination
Clark, Joseph R.,Dixon, Charlie F.,Feng, Kaibo,Han, Wei,Ide, Takafumi,Koch, Vanessa,Teng, Dawei,Wendell, Chloe I.,White, M. Christina
supporting information, p. 14969 - 14975 (2021/10/01)
Allylic amination enables late-stage functionalization of natural products where allylic C-H bonds are abundant and introduction of nitrogen may alter biological profiles. Despite advances, intermolecular allylic amination remains a challenging problem due to reactivity and selectivity issues that often mandate excess substrate, furnish product mixtures, and render important classes of olefins (for example, functionalized cyclic) not viable substrates. Here we report that a sustainable manganese perchlorophthalocyanine catalyst, [MnIII(ClPc)], achieves selective, preparative intermolecular allylic C-H amination of 32 cyclic and linear compounds, including ones housing basic amines and competing sites for allylic, ethereal, and benzylic amination. Mechanistic studies support that the high selectivity of [MnIII(ClPc)] may be attributed to its electrophilic, bulky nature and stepwise amination mechanism. Late-stage amination is demonstrated on five distinct classes of natural products, generally with >20:1 site-, regio-, and diastereoselectivity.
Asymmetric Nazarov Cyclizations Catalyzed by Chiral-at-Metal Complexes
Mietke, Thomas,Cruchter, Thomas,Larionov, Vladimir A.,Faber, Tabea,Harms, Klaus,Meggers, Eric
, p. 2093 - 2100 (2018/04/19)
The application of Lewis acidic chiral-at-metal complexes of iridium(III) and rhodium(III) as catalysts for the asymmetric polarized Nazarov cyclization of dihydropyran- and indole-functionalized α-unsaturated β-ketoesters is reported (overall 24 examples). For both substrate classes, catalyst loadings of 2 mol% were found to be sufficient for achieving high yields and high stereoselectivities. The cyclized dihydropyran products were isolated in 85–98% yield, with 89%–>99% ee, and trans/cis ratios of 15:1–50:1 (9 examples). The cyclized indole products were typically isolated in more than 70% yield and in up to 93% yield, typically with more than 90% ee and in up to 97% ee, and trans/cis ratios of 12:1–28:1 (15 examples). (Figure presented.).
The first calcium-catalysed Nazarov cyclisation
Davies, Jacob,Leonori, Daniele
, p. 15171 - 15174 (2014/12/11)
The first calcium-catalysed Nazarov cyclisation is described. The Ca(NTf2)(PF6) complex is found to be a very active catalyst for 4π electrocyclisations. The remarkable catalytic activity of this complex is attributed to its increased Lewis acidity compared to other Ca complexes. Spectroscopic studies have provided an insight into the chelating interactions between the substrate and the Ca catalyst.
The naturally occurring ketene acetal benesudon: Total synthesis and assignment of relative and absolute stereochemistry
Clive, Derrick L. J.,Minaruzzaman,Yang, Haikang
, p. 6743 - 6752 (2008/12/23)
(Chemical Equation Presented) The densely functionalized ketene acetal benesudon, which is a bioactive fungal metabolite, was synthesized from D-glucose by a route involving radical cyclization to form the five-membered ring, and oxidative decarboxylation
HETEROCYCLISATIONS DES HYDROXY-6 METHOXY-2 HEXENE-2 ET HEPTENE-2 OATES DE METHYLE.
Faivre, Veronique,Lila, Christine,Saroli, Alfred,Doutheau, Alain
, p. 7765 - 7782 (2007/10/02)
Tetrahydropyran derivatives 14-17 and 22-25 are formed in good yields by cyclisation of methyl-6-hydroxy-2-hexenoate 6 or 2-heptenoate 7 mediated by various electrophilic reagents (mCPBA, benzeneselenyl chloride, N-bromosuccinimide, iodide).Cyclisations o
