Ru(phen)3 Cl2 -Catalyzed Chlorotrifluoromethylation of Unactivated Alkenes.

A novel Ru(phen)3 Cl2 -catalyzed free-radical chlorotrifluoromethylation reaction of unactivated olefins was investigated. Substituted 8-aminoquinoline-derived inert enamides were reacted with the Togni regent to afford a broad range of Cl-containing trifluoromethyl derivatives in good yields. The reaction proceeded at 90 °C and experimental result shows that the chlorine source of the products originated from LiCl.

Copper(i)-catalyzed radical carboamination reaction of 8-aminoquinoline-oriented buteneamides with chloroform: synthesis of-ß-lactams.

A novel Cu(CH3CN)4PF6-catalyzed carboamination reaction of 8-aminoquinoline-oriented buteneamides with chloroform to afford 4-(2,2,2-trichloroethyl)-ß-lactams is described. The reaction proceeded at 110 °C in air with di-t-butyl peroxide. Preliminary studies indicated that the reaction undergoes a free radical mechanism via a Cu(i)/Cu(ii)/Cu(iii) catalytic cycle.

Nickel-Catalyzed, para-Selective, Radical-Based Alkylation of Aromatic Ketones.

A direct, para-selective, radical-based alkylation of aromatic ketones with alkanes has been developed using a nickel catalyst with oxamide as the ligand. Acetophenones bearing electron-withdrawing substituents were functionalized directly with simple alkanes with high para-selectivity while acetophenones with electron-donating groups were mainly para-functionalized. A mechanistic study indicated that C-H bond activation of the aromatic ring may be the rate-determining step of the reaction.

Mn-Enabled Radical-Based Alkyl-Alkyl Cross-Coupling Reaction from 4-Alkyl-1,4-dihydropyridines.

Highly efficient alkylation of ß-chloro ketones and their derivatives was achieved by means of domino dehydrochlorination/Mn-enabled radical-based alkyl-alkyl cross-coupling reaction. In situ-generated α,ß-unsaturated ketones and their analogues were identified as the reaction intermediates. Known bioactive compounds, such as melperone and azaperone, could be easily prepared from ß-chloropropiophenone in two steps.

Palladium-Catalyzed Carboxylate-Assisted Ethoxycarboxylation of Aromatic Acids To Synthesize Monoethyl Phthalate Derivatives with Ethyl Bromodifluoroacetate.

A novel and efficient approach for direct carbonation of aromatic acids with ethyl bromodifluoroacetate as the carbonyl source is reported. A broad range of substrates bearing various functional groups were tolerated, leading to monoalkyl phthalate derivatives in moderate to good yields.

A practical copper-catalyzed approach to ß-lactams via radical carboamination of alkenyl carbonyl compounds.

Functionalized ß-lactams are highly important motifs in synthetic chemistry. We report an efficient and novel approach to the synthesis of ß-lactams via a copper(i)-catalyzed cascade process involving C(benzyl)-H radical abstraction, intermolecular alkene addition, and intramolecular amination reaction. Variously substituted alkenes were synthesized from vinylacetic acid, leading to the corresponding ß-lactams in moderate to good yields. Preliminary studies indicate that the reaction undergoes a free radical mechanism via a Cu(i)/Cu(ii)/Cu(iii) catalytic cycle.

Direct ortho-Selective C-H Functionalization of Carboxybenzyl-Protected Arylalkylamines via Ir(III)-Catalyzed C-H Activation.

A convenient and practical approach to synthesize ortho-alkynylated arylalkylamines through ortho-selective C-H functionalization has been developed using Cbz-amide as the directing group and Ir(III) as the catalyst. Various substrates were well tolerated, affording the corresponding products in moderate to good yields. Moreover, preliminary mechanistic study revealed the role of the amide as the coordination center to cooperate with the Ir(III) complex during C-H activation. Development of this Cbz-amide-promoted CAr-H functionalization offers a practical approach with potential applications in organic synthesis.

Ruthenium(II)-Catalyzed C-H Difluoromethylation of Ketoximes: Tuning the Regioselectivity from the meta to the para Position.

A highly para-selective CAr -H difluoromethylation of ketoxime ethers under ruthenium catalysis has been developed. A wide variety of ketoxime ethers are compatible with the reaction, which leads to the corresponding para-difluoromethylated products in moderate to good yield. A mechanistic study clearly showed that chelation-assisted cycloruthenation is the key factor in the para selectivity of the difluoromethylation of ketoxime ethers. Density functional theory was used to gain a theoretical understanding of the para selectivity.

Copper(i) reagent-promoted hydroxytrifluoromethylation of enamides: flexible synthesis of substituted-3-hydroxy-2-aryl-3-(2,2,2-trifluoro-1-arylethyl)isoindolin-1-one.

A novel CuBr-catalyzed hydroxytrifluoromethylation reaction was investigated. Substituted 3-benzylidene-2-arylisoindolin-1-ones was reacted with sodium trifluoromethanesulfinate to afford substituted-3-hydroxy-2-aryl-3-(2,2,2-trifluoro-1-arylethyl)isoindolin-1-one. The reaction proceeded at 25 °C in air atmosphere in the absence of base and ligands. Our results indicate that trifluoromethyl free radical tends to attack a double bond rather than aryl in this reaction.

Pd-Catalyzed Coupling of γ-C(sp(3))-H Bonds of Oxalyl Amide-Protected Amino Acids with Heteroaryl and Aryl Iodides.

Pd-catalyzed regioselective coupling of γ-C(sp(3))-H bonds of oxalyl amide-protected amino acids with heteroaryl and aryl iodides is reported. A wide variety of iodides are tolerated, giving the corresponding products in moderate to good yields. Various oxalyl amide-protected amino acids were compatible in this C-H transformation, thus representing a practical method for constructing non-natural amino acid derivatives.

Palladium-Catalyzed Oxalyl Amide-Directed γ-Arylation of Aliphatic Amines.

A method for palladium-catalyzed oxalyl amide-directed arylation of α-unsubstituted aliphatic amines with aryl iodides has been developed. A wide variety of aryl iodides are tolerated in this transformation, affording various γ-arylpropylamine derivatives. Heterocyclic iodides can also be competent reagents in this γ-C(sp(3))-H bonds transformation.

Palladium-catalyzed oxalyl amide assisted direct ortho-alkynylation of arylalkylamine derivatives at δ and ε positions.

Palladium-catalyzed oxalyl amide directed ortho-alkynylation of arylalkylamine derivatives is reported for the first time. A wide variety of ß-arylethamine and γ-arylpropamine derivatives are compatible with this protocol. This method provides a general means to synthesize substituted alkynylarylalkylamine derivatives, highlighting the ability of oxalyl amide in promoting C-H functionalization at unique δ and ε positions.

CoPc-catalyzed selective radical arylation of anilines with arylhydrazines for synthesis of 2-aminobiaryls.

CoPc-catalyzed selective radical arylation of anilines with arylhydrazines to afford 2-aminobiaryls in moderate to good yields is described.

Copper-catalyzed coupling reaction of arylhydrazines and trialkylphosphites.

A novel CuO-catalyzed coupling reaction of arylhydrazines with trialkyl phosphites to afford arylphosphonates is described. The reaction proceeded at 80 °C in air without external reductants, oxidants, and ligands.

[Clinical analysis of multiple organ dysfunction syndrome caused by acute paraquat poisoning].

OBJECTIVE: To analysis clinical characteristics of the multiple organ dysfunction syndrome (MODS) caused by acute paraquat poisoning (APP). METHOD: Clinical data of 68 APP cases from Jan 2006 to Jun 2009, including age, gender, poisoning time and dosage, and MODS time, were compared in two groups, i.e. the death (37 cases) and survived (31cases) groups. It was less than 24 hours from poisoning to rescue in all cases. RESULTS: Among the 68 cases, the incident rate of ARDS was 51.47% (35 cases). The rate of acute lung injure was 97.1% (66 cases). The mortality was 54.4% (37 cases). There was no significant difference in age and gender between both groups (P > 0.05). The dosages and times from poisoning to rescue were significant different between two groups (P < 0.05, P < 0.01). In the death group, proportion of amounts (> 3) of organs related with MODS was 70.29%, which was significantly higher than that (38.71%) in survived group (P < 0.01). MODS and ALI/ARDS occurred in death group earlier than those in survival group (P < 0.05). On the other hand, cardiac, hepatic and renal damage occurred earlier than the lung injure. CONCLUSION: MODS in APP patients occurred earlier, were more sever, and caused higher mortality. The poisoning dosage and time were important prognostic factors.

Novel synthesis of 1-aroyl-3-aryl-4-substituted imidazole-2-thiones.

[reaction: see text] An efficient route to 1-aroyl-3-aryl-4-substituted imidazole-2-thiones (2, 4-6) has been developed. The methodology involves the cyclization of 1-aroyl-3-arylthioureas with a variety of carbonyl compounds bearing alpha-H in the presence of bromine and triethylamine.