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A novel and efficient N-arylation of trifluoromethylated N-acylhydrazones is described by using diaryliodonium salts as arylation reagents in the presence of copper salts. A wide variety of N-aryl acylhydrazones are obtained with good to excellent yields under mild reaction conditions.

A novel and efficient protocol for the construction of trifluoroethyl pyrazolines has been developed by cascade cyclization/trifluoromethylation reaction of β,γ-unsaturated hydrazones. This strategy uses cheap and commercially available trichloroisocyanuric acid as promoter and TMSCF3 as the trifluoromethylating reagent, which make the trifluoromethylating process much cheaper. A wide range of substrates can be applied in this process to afford the trifluoroethyl pyrazolines in good yield.

A simple and efficient method for the visible light induced direct carbon alkylation of quinoxalin-2(1H)-ones at the C3 position is described. This protocol employs cheap and readily available phenyliodine(III) dicarboxylates as the alkylation reagents to conduct decarboxylative radical coupling reaction with quinoxalin-2(1H)-ones. The process exhibits excellent compatibility to functional groups and provides a convenient and selective access to various 3-alkylquinoxalin-2(1H)-ones in good yields.

Given the versatility and value of the structurally diverse organohalides and CF3-containing compounds in organic synthesis, we reported a green, oxidant-free electrochemical method using undivided electrochemical cells for radical bromination, chlorination and trifluoromethylation–formyloxylation of the various alkenes with readily available halogen radical (NaCl, NaBr), trifluoromethyl radical (CF3SO2Na) sources, and DMF as formyloxylation reagents. The protocol is operationally simple and robust and the Cl–, Br– or CF3– was directly oxidized at the anode, obviating the need for exogenous chemical oxidants.

A CuI promoted sulfenylation of organozinc reagents with arylsulfonyl chlorides/PPh3 has been explored. This reaction proceeded smoothly through an alkyl/aryl radical (generated from organometallics) under mild conditions and produced the desired sulfide products in excellent yields.

A magnesium salt promoted synthesis of ketones via tandem nucleophilic addition-Oppenauer oxidation of aldehydes using organozinc chemistry was demonstrated. Magnesium salts concomitantly generated via magnesium metal mediated organohalide zincation exhibit high efficacy for nucleophilic addition of organozinc reagents to aromatic aldehydes and thereafter Oppenauer oxidation whereby ketones are formed in high to excellent yields.

Reformatsky reagent, benzylzinc bromide or alkylzinc iodides react with aryl isocyanates directly to give corresponding N-substituted carbamates under mild reaction conditions. However, the reaction of allylzinc bromide or propargylzinc bromide with aryl isocyanates produces the corresponding N-substituted amides. The reactions provide alternative methods for the synthesis of N-substituted carbamates or amides.

Bifunctional chiral thioureas have been successfully used as organocatalysts in enantioselective fluorinations of β-keto esters. The corresponding products could be obtained with good to excellent enantioselectivity in high yields by using N-fluorobisbenzenesulphonimide (NFSI) as fluorination reagent.

In the presence of a silylating reagent and catalytic amount of Ni(acac)2, organozinc halides reacted with aromatic aldehydes to give the corresponding dialkylation products in good to excellent yields under mild conditions.

The efficient olefination from organozinc reagents with aldehydes is exploited in a new synthesis of aryl and alkyl olefins.

Condensation of cycloalkanone with aromatic aldehyde and furfural using supported reagents to prepare bis(substituted benzylidene or furfurylidene)cycloalkanone in excellent yields under microwave irradiation.

The title reaction provides access to a series of alkyl, aryl and hetaryl sulfones (III) and (V) bearing various kinds of functional groups.

Aluminium powder has been used to reduce titanium tetrachloride to generate the low valent titanium (LVT)reagent which can induce the reductive coupling of aldehydes and ketones to form the corresponding pinacols or olefins. However, arylsulfonyl chlorides will give diaryldisulfides under the same condition.

The present new method proceeds in the presence of trimethylsilyl chloride which acts as an essential reaction promoter and a protection reagent for the sensitive N-hydroxylamine group.

Bifunctional chiral thioureas have been successfully used as organocatalysts in enantioselective fluorinations of β-keto esters. The corresponding products could be obtained with good to excellent enantioselectivity in high yields by using N-fluorobisbenzenesulphonimide (NFSI) as fluorination reagent.

An efficient catalytic 1,4 addition reaction of functionalised organozinc reagents with enones has been developed using a nickel complex as catalyst.

The transmetalation of functionalized organozinc iodides with Cu(OAc)2 in THF provides a new convenient method for the preparation of functionalized organozinc-copper(I) reagents FG-RCu(OAc)ZnI which ultimately undergo 1,4-addition reaction with enones to give the products in good to excellent yields.

Aluminium powder has been used to reduce titanium tetrachloride to generate the low valent titanium (LVT)reagent which can induce the reductive coupling of aldehydes and ketones to form the corresponding pinacols or olefins. However, arylsulfonyl chlorides will give diaryldisulfides under the same condition.

Aluminium powder has been used to reduce titanium tetrachloride to generate the Low-valent Titanium reagent (LVT); the reactions of substituted nitrobenzenes induced by LVT are described and the reaction mechanism is briefly discussed.

A palladium-catalysed cross-coupling reaction of sodium tetraphenylborate with aroyl chloride using KF/Al2O3 as supported reagents in the presence of acetone under microwave-irradiation conditions gives unsymmetrical ketones in good high yield.

Condensation of cycloalkanone with aromatic aldehyde and furfural using supported reagents to prepare bis(substituted benzylidene or furfurylidene)cycloalkanone in excellent yields under microwave irradiation.

A powerful reagent, P[NCH(3)(OCH(3))](3) (3), for conversion of carboxylic acids directly to Weinreb amides was developed. In most cases the yields of the corresponding Weinreb amides were above 90% when P[NCH(3)(OCH(3))](3) was heated with aromatic and aliphatic carboxylic acids in toluene. The sterically hindered carboxylic acids can also give the corresponding Weinreb amides in excellent yields.

In the presence of a silylating reagent and catalytic amount of Ni(acac)2, organozinc halides reacted with aromatic aldehydes to give the corresponding dialkylation products in good to excellent yields under mild conditions.

In the presence of a catalytic amount of PdCl 2 (PPh 3 ) 2 and a silylating agent, organozinc halides reacted with carbonyl compounds to give the corresponding (E)-stilbenes in good to excellent yields under mild conditions. The reaction mechanism is briefly discussed.

The efficient olefination from organozinc reagents with aldehydes is exploited in a new synthesis of aryl and alkyl olefins.

In the presence of pinacolone, the in situ prepared triorganoaluminium reagents reacted with aromatic aldehydes to give ketones in moderate to high yield. We propose that the products are formed via a tandem organoaluminium reagents addition-Oppenauer oxidation sequence.

A palladium-catalysed cross-coupling reaction of sodium tetraphenylborate with aroyl chloride using KF/Al2O3 as supported reagents in the presence of acetone under microwave-irradiation conditions gives unsymmetrical ketones in good high yield.

Aluminium powder has been used to reduce titanium tetrachloride to generate the Low-valent Titanium reagent (LVT); the reactions of substituted nitrobenzenes induced by LVT are described and the reaction mechanism is briefly discussed.