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Asymmetric total synthesis of (−)-javaberine A and its epimer was achieved by utilizing two methods for isoquinoline synthesis, asymmetric hydroamination of N-methyl-2-(2-styrylaryl)ethylamine and Bischler-Napieralski cyclization. Intramolecular asymmetric hydroamination of N-methyl aminoalkene 4 was catalyzed by lithium amide–chiral bisoxazoline to give tetrahydroisoquinoline (S)-laudanosine with good enantioselectivity in excellent yield. N-Demethylation of (S)-laudanosine was accomplished by Polonovski-type reaction to give (S)-norlaudanosine. Condensation of (S)-norlaudanosine with homoveratric acid, and subsequent Bischler-Napieralski cyclization, LiAlH4 reduction, and O-demethylation furnished (8R,14S)-(−)-javaberine A, corresponding to antipode of natural javaberine A. (8S,14S)-(−)-Javaberine A, which corresponds to C14-epimer of natural javaberine A, was also successfully synthesized.

A novel etherification of 2-hydroxy-1,4-naphthoquinone derivatives with alkoxyalkyl chlorides and hydride bases is described. Precise study of the conditions and substrate scope suggested that the reaction occurs specifically in the molecule having a 2-hydroxy-1,4-benzoquinone skeleton. A chemoselective O-methylation reaction was achieved to afford a synthetically important intermediate, which offered easy access to a natural product possessing anti-tumor activity.

Described here is the first enantioselective total synthesis of lantalucratin C, which was isolated from the rainforest plant Lantana involucrata, and which possesses anti-tumor activity. The OH group on the aromatic ring was systematically introduced by an appropriate management of the OH protecting groups. The alkyl side chain connected to a chiral carbon center was incorporated by directed ortho-lithiation of naphthalenes followed by asymmetric epoxidation. The furano-1,2-naphthoquinone skeleton was constructed from 3-hydroxyalkylnaphthalene by CAN-mediated oxidative cyclization. The absolute stereochemistry at the C2 carbon was assigned the R-configuration by the Kusumi–Mosher method.

The oxidative intramolecular cyclization of 3-hydroxyalkyl-1,2,4-trimethoxynaphthalenes was investigated. A series of 1,2-naphthoquinone fused cyclic ethers were synthesized directly from 3-hydroxyalkyl-1,2,4-trimethoxynaphthalenes by exposure to diammonium cerium (IV) nitrate. To understand the reaction mechanism, the intramolecular cyclization of 3-hydroxyalkyl-naphthoquinones that were formed as reaction intermediates was also examined. The results suggested that the reaction proceeds by a stepwise oxidation–cyclization mechanism. Using this methodology, five-step synthesis of rhinacanthone was achieved with high yield.

The first total synthesis of (±)-lantalucratins A and B is described. Introduction of an alkyl side chain at the 6-position was proceeded by directed ortho -lithiation and subsequent alkylation reaction to afford 6-alkyl-5,7,8-trimethoxy-1-naphthol as a synthetically important intermediate for (±)-lantalucratins A and B in excellent yield with complete regioselectivity. The 1,2-naphthoquinone fused five-membered cyclic ether framework was constructed directly from 3-hydroxyalkyl-naphthalenes by oxidative intramolecular cyclization reaction with diammonium cerium(IV) nitrate. (±)-Lantalucratins A and B were obtained in 69% and 45% overall yields, respectively.

A concise method has been developed for the synthesis of caroverine and its derivatives. The quinoxalinone scaffold of these compounds was constructed via the tandem nitrosation/aerobic oxidative C N bond formation reaction of N -(2-chloroethyl)-2-cyano- N -phenylacetamide, followed by sequential Grignard, Finkelstein and nucleophilic substitutions reactions to give several different derivatives. Herein, we describe the development of this strategy in terms of the optimization of each step as well as the effect of different additives on the individual reactions.

Consecutive cyclization of allylaminoalkenes by tandem aminolithiation-carbolithiation proceeded smoothly by using a lithium amide as a lithiating agent as well as protonating agent to give bicyclic amines, octahydroindolizine and hexahydro-1 H-pyrrolizine, in reasonably high yield and diastereoselectivity.

A simple method for the direct synthesis of 2,2′-binaphthols 2 and dinaphtho[1,2-b;2′,1′-d]furans 3 under mild conditions was developed, utilizing a biaryl coupling reaction via electron donor–acceptor complexes of 1-naphthols with SnCl4. Heating of the complex in a sealed tube for (18–24 h) afforded the corresponding o–o coupled product 2 in excellent yield. Prolonged reaction (56–65 h) under the same conditions afforded 3 in high yield in one step. We also found that in the case of α-naphthol without substituents other than a hydroxyl group at the C-1 position, regioselective o–o coupling reaction proceeded. The products 2a, 2b and 2g should be useful as synthetic intermediates for naturally occurring 3,3′-bijuglone, 3,3′-biplumbagin and elliptinone.

The first total and biomimetic synthesis of violet-quinone ( 1 ), which has a dinaphthofuranquinone (DNFQ) framework, is described. This synthesis features the oxidative dimerization of 1-naphthol 4 and the construction of the DNFQ framework by photochemical ring closure of 2,2′-binaphthoquinone 7 as a key intermediate. Compound 7 was prepared by the novel oxidative dimerization of 4 with a semiconductor (such as ZrO 2 ) in the presence of dioxygen, followed by oxidation of the resulting 2,2′-binaphthyl-1,1′-quinone 6 with HNO 3 .

Asymmetric intramolecular cyclization of aminoalkenes was catalyzed by a catalytic amount of n -butyllithium, diisopropylamine, and a newly designed chiral bisoxazoline in toluene to produce kinetically controlled exo -cyclized amines with up to 91% ee quantitatively.

Mild palladium-catalyzed aminations of aryl tosylates and the first aminations of heteroaryl tosylates are described. In the presence of the combination of L2Pd(0) (L = P(o-tol)3) and the hindered Josiphos ligand CyPF-t-Bu, a variety of primary alkylamines and arylamines react with both aryl and heteroaryl tosylates at room temperature to form the corresponding secondary arylamines in high yields with complete selectivity for the monoarylamine. These reactions at room temperature occur in many cases with catalyst loadings of 0.1 mol % and 0.01 mol % in one case, constituting the most efficient aminations of aryl tosylates by nearly 2 orders of magnitude. This catalyst is made practical by the development of a convenient method to synthesize the L2Pd(0) precursor. This complex is stable to air as a solid. In contrast to conventional relative rates for reactions of aryl sulfonates, the reactions of aryl tosylates are faster than parallel reactions of aryl triflates, and the reactions of aryl tosylates are faster than parallel or competitive reactions of aryl chlorides.

A simple method was developed for the direct synthesis of 2,2′-binaphthoquinones and dinaphtho[1,2-b;2′,1′-d]furans, utilizing an oxidative reaction via electron donor–acceptor complexes of 1-naphthols with SnCl4 in the absence or presence of dioxygen. As an application of this method to natural product synthesis, we describe a facile biomimetic synthesis of several binaphthoquinones, 3,3′-bijuglone, 3,3′-biplumbagin and elliptinone.

We describe a systematic study of the scope and relationship between ligand structure and activity for a highly efficient and selective class of catalysts containing sterically hindered chelating alkylphosphines for the amination of heteroaryl and aryl chlorides, bromides, and iodides. In the presence of this catalyst, aryl and heteroaryl chlorides, bromides, and iodides react with many primary amines in high yields with part-per-million quantities of palladium precursor and ligand. Many reactions of primary amines with both heteroaryl and aryl chlorides, bromides, and iodides occur to completion with 0.0005-0.05 mol % catalyst. A comparison of the reactivity of this catalyst for the coupling of primary amines at these loadings is made with catalysts generated from hindered monophosphines and carbenes, and these data illustrate the benefits of chelation. Studies on structural variants of the most active catalyst indicate that a rigid backbone in the bidentate structure, strong electron donation, and severe hindrance all contribute to its high reactivity. Thus, these complexes constitute a fourth-generation catalyst for the amination of aryl halides, whose activity complements catalysts based on monophosphines and carbenes.