Nicolaou, K. C. published the artcileRapid access to complex molecular architectures via o-azaquinones, Category: catalysis-chemistry, the publication is Angewandte Chemie, International Edition (2001), 40(11), 2145-2149, database is CAplus and MEDLINE.
Complex analogs I and II of pseudopterosin and elisabethin natural products, resp., were prepared in a single step from the amidoaryldiene 4-[Me2CHC(:O)NH]C6H4(CH2)3CH:CHCH:CH2 (III) in a single step by oxidation with the Dess-Martin periodinane, allowing rapid access to natural product analogs from simple starting materials. E.g., III was prepared in 5 steps and 72% overall yield from 4-(4-aminophenyl)butanoic acid by LAH reduction of the acid to a primary alc., acylation of both the aniline and alc. moieties with isobutyryl chloride followed by hydrolysis of the ester with sodium hydroxide in methanol, oxidation of the primary alc. with o-iodooxybenzoic acid, and Horner-Wittig olefination of the aldehyde with di-Ph allyl phosphine oxide. E.g., treatment of III with 4 equivalent of the Dess-Martin periodinane and 2 equivalent of water presumably generated the key ortho-azaquinone moiety in situ; oxidation of the o-azaquinone followed by intramol. Diels-Alder cycloaddition gave benz[d]indene dione (and elisabethin analog) II in 25% yield, while intramol. Diels-Alder cycloaddition followed addition of water to the remaining imine moiety gave hexahydrophenalenone derivative (and pseudopterosin analog) I in 28% yield. I could be functionalized with various reagents to give various polycyclic natural product-like derivatives Condensation of I with aryl amines in the presence of pyridinium tosylate yielded aromatized derivatives IV [R = 2-HO-5-MeC6H3, 5-indazolyl, 2-(EtO2C)C6H4, Ph] in 45-84% yields, while treatment of I with the hydrochlorides of amino acid esters R1CH(NH2)CO2Me [R1 = 4-HOC6H4, PhCH2, Me2CH, EtO2CCH2CH2, Me, MeSCH2CH2, CbzNH(CH2)4] in the presence of pyridinium tosylate gave the fused oxazinones V in 49-80% yields, and condensation of I with diamines gave pyrazine derivatives such as VI in 73-94% yields. Condensation of I with nonracemic 1,2-aminoalcs. in the presence of pyridinium tosylate gave spirooxazole derivatives such as VII in 66-87% yields. Oxazinone and pyrazine fused derivatives such as VI can be aromatized by heating in air in either DMF or toluene solution The solid-phase preparation of combinatorial libraries of natural product-like compounds such as I and its functionalized derivatives is being explored (no data).
Angewandte Chemie, International Edition published new progress about 4141-48-4. 4141-48-4 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Allyldiphenylphosphine oxide, and the molecular formula is C15H15OP, Category: catalysis-chemistry.
Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia