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N-Alkyl-N-(2-vinylbenzyl)prop-2-en-1-amine derivatives undergo a one-pot olefin isomerization/aliphatic enamine ring-closing metathesis (RCM)/oxidation/1,3-dipolar cycloaddition sequence with the ruthenium complex, Ru(CO)HCl(PPh3)3, a second generation Hoveyda–Grubbs catalyst, and a 1,3-dipolarophile. Overall, in a single operation the reaction sequence converts simple benzylamine derivatives into isoindolo[1,2-a]isoquinolines with a π-conjugated four-ring system, through three unique ruthenium-catalyzed transformations.

Based on a tandem oxidation/aldol condensation reaction meso-1,4-tetralinediol is efficiently converted according to the title reaction.

The title method involves stereocomplementary N-methylimidazole-mediated enol tosylations, as well as stereoretentive Suzuki—Miyaura cross-couplings.

Asymmetric tandem coupling of meso-diols (I) with aldehydes is achieved using a chiral Ir-catalyst.

structure elucidation and cytotoxic activity of new cholestane glycosides (I)—(III) to HL-60 cells

As a new organic reaction medium, a periodic mesoporous inorganic material was found to function as a “solid solvent” in a Diels–Alder reaction of C60 with cyclopentadiene. This finding was supported by a concentration effect and a kinetic study of the reaction.

An enantioselective intramolecular Wacker-type cyclization of 2-alkenyl-1,3-diketones catalyzed by a Pd(II)−SPRIX complex was developed. The reaction proceeded in a 6-endo-trig mode to give the des...

Palladium-catalyzed intramolecular oxidative Wacker-type cyclization of o-geranylphenols (I) predominantly provides access towards chromenes (II) via a 6-endo-trig pathway.

( S ) Propranolol, a more potent optical isomer of the widely used β-blocker, was conveniently synthesized in a higly enantioselective manner by the lanthanum-( R )-(+)-binaphthol complex catalyzed asymmetric nitroaldol reaction.

The optically active La complex, which catalyzes asymmetric nitroaldol reactions, was found to be readily prepared from LaCl3·7H2 O. The presence of water, LiCl or LiBr and an alkali metal hydroxide was essential for the formation of the effective lanthanum binaphthoxide complex.

An efficient synthesis of (−)-pindolol, an effective β-blocker, has been achieved utilizing a lanthanum-lithium-( R )-BINOL (( R )-LLB) catalyzed nitroaldol reaction as a key step. This methodology was applicable to a synthesis of 13 C-labeled (−)-pindolol, which would be useful as a biological tool for tracing the metabolism of β-blocker and 5-HT 1A receptor antagonist. The mechanistic aspects of the LLB catalyzed nitroaldol reaction are also discussed.

Rare earth-Li-BINOL complexes were used to catalyze nitroaldol reactions of optically active α-amino-aldehydes with nitromethane in a highly diastereoselective manner. A typical adduct, (2S, 3S)-3-phthaloylamino-2-hydroxy-1-nitro-4-phenylbutane was conveniently converted to (2S, 3S)-3-amino-2-hydroxy-4-phenylbutanoic acid (erythro-AHPA ; phenylnorstatine), a component of the HIV protease inhibitor KNI-227 and KNI-272.

The La-Li-(R)-BINOL complex prepared from either lanthanum(III) chloride [LaCl 2 .7H 2 O] or [La(O-i-Pr) 3 ] has made possible effective catalytic asymmetric syntheses of therapeutically important β-blockers such as propranolol and metoprolol. The possible stereochemical course of asymmetric nitroaldol reactions has been also clarified

A new approach was proposed for the DC-plasma-assisted ceramic synthesis using liquid as starting materials. The method consists of generating a plasma between the substrate (electrode) and the liquid phase. Plasma-assisted deposition above the liquid surface of a water-ethylene glycol solution yielded diamond on anode substrate under a constant applied voltage. The morphology and quality of diamond changed from mirror-ball particle with disordered graphite to high-quality film with prolonged deposition. Heating a cathode wire by discharge in an aqueous solution of aluminum nitrate produced α-alumina coatings without post-annealing under atmospheric pressure. Deposition stopped automatically when the whole wire in the solution was covered with alumina. The growth rate of the alumina coatings ranged 1–10 μm min −1 .

A chiral hydrobenzoin/Ca complex catalyzes the reaction of acetophenone and aliphatic aldehydes to give the corresponding aldol products in up to 91% ee.

Catalytic asymmetric Michael reaction of β-keto esters and methyl vinyl ketone was achieved using a chiral diamine-based Rh complex to give the Michael adducts in up to 75% e.e.

An anti-selective direct catalytic asymmetric aldol reaction of 2-hydroxyacetophenones with aldehydes is described. The reaction is catalyzed by a heteropolymetallic complex to afford anti-α,β-dihydroxy ketones as the major diastereomer with excellent enantioselectivity. The use of 2-hydroxyacetophenones bearing electron-donating groups at the phenyl moiety enabled efficient transformation of the aldol products (α,β-dihydroxy ketones) into the corresponding α,β-dihydroxy ester derivatives via Baeyer−Villiger oxidation. A plausible reaction mechanism is also discussed based on the stereochemistry of the products.

A novel amino alcohol-based Ir bifunctional complex acts as an efficient catalyst for oxidative lactonization of 1,4- or 1,5-diols with a substrate-to-catalyst molar ratio of 200−1000 in acetone or butanone. The reaction proceeds with broad functional group tolerance to give lactone in high yield at room temperature. The catalyst precursor Cp*IrCl[OCH2C(C6H5)2NH2] is isolated and characterized by a single-crystal X-ray analysis.

This account focuses our works on the development of chiral spiro ligands bearing N-heterocycles as metal-coordinating units and their applications in the metal-catalyzed asymmetric reactions. The ...

Preparation and structural analysis of chiral dinuclear vanadium(v) catalysts with high catalytic activity for the oxidative coupling of 2-naphthols are described.

Novel chiral spiro bis(isoxazoline) ligands 3 and 4 are synthesized from an optically active olefin. The Cu(II)-spiro bis(isoxazoline) complex prepared in situ from Cu(OTf)2 and 3 promoted the glyoxylate-ene reaction in high yield and moderate enantioselectivity (up to 70%).

cis-3,4-bis[(E)-1-butenyl]tetrahydro-2-furanol, the pheromone of the Biprorulus bibax, was synthesized by the iridium catalyzed oxidative lactonization.

The first total synthesis of (−)-nalanthalide (1), a novel blocker of the voltage-gated potassium channel Kv1.3 from a microorganism, was accomplished in a convergent manner by utilizing coupling reaction of the trans-decalin 5 with 3-lithio-γ-pyrone 4. The key intermediate 5 was efficiently prepared from the known trans-decalone 7 through a [2,3]-Wittig rearrangement of the stannylmethyl ether 6 to install the stereogenic center at C9 and the exo-methylene function at C8.

Tishchenko reaction of aldehydes in the presence of an amino alcohol-based Ir bifunctional catalyst was developed. The reaction proceeds with 1 mol% of the catalyst and 20-30 mol% of K 2 CO 3 in acetonitrile at room temperature to give the corresponding dimeric esters in good yield.

Two new cyclizations of ketoaldehydes have been developed using an Ir-ligand bifunctional catalyst. Oxidative lactonization of delta-ketoaldehydes proceeded smoothly at room temperature to give coumarin derivatives in excellent yields. Intramolecular Tishchenko reaction of delta-ketoaldehydes afforded 3,4-dihydroisocoumarins in good yields.

A chiral amino alcohol/Ir complex catalyzes the asymmetric oxidative lactonizations of meso-diols to give the corresponding lactones in up to 81% ee.