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An efficient organocatalytic method was developed for synthesizing functionalized spiropyrazolone derivatives containing four contiguous stereogenic centres by using a Michael-aldol consecutive reaction. We applied a quinine-derived squaramide catalyst to catalyze a reaction between 3-methyl-1-aryl-2-pyrazolin-5-ones and (E)-5-nitro-6-aryl-hex-5-en-2-ones, realizing the desired spiropyrazolones in moderate-to-good yields (up to 80%) with good-to-excellent stereoselectivities (up to >20 : 1 dr, 94% ee).

An efficient copper-catalyzed reaction for the synthesis of benzisothiazol-3(2H)-ones has been developed, starting from easily available 2-halobenzamides and carbon disulfide, which gave the corresponding target products in 30–89% yield for 25 examples. The reaction proceeds via a consecutive process with S–C bond and S–N bond formation.

An efficient and practical copper-catalyzed consecutive synthesis of quinazolin-4(3 H )-ones and pyrido[2,3- d ]pyrimidin-4(3 H )-ones from easily available 2-halobenzamides (or 2-halonicotinamides), aldehydes, and sodium azide has been developed, which gave the corresponding target products in 50–95% yields for 29 examples. This remarkable consecutive process involved sequential copper-catalyzed S N Ar, reduction, cyclization, and oxidation. Notably, this work would provide a novel synthetic strategy for bioactive molecules containing quinazolinone class skeletons.

In contrast to previous reports concerning alkyl-substituted sulfoxides, the reactions of aryl-substituted substrates with lithium acetylides produce (Z)-enediynes instead of the expected conjugated enynes.

Facile and efficient procedures for the N-acylation reaction of amide derivatives with various acid anhydrides and the cyclization reaction of N-acylated amide derivatives with various hydrazine hydrochlorides were described. The reactions were carried out under microwave irradiation to give products in good yields in a few minutes. The synthesis of 1,3,5-trisubstituted-1,2,4-triazoles from benzamides can also be accomplished in a simple one-pot sequential reaction.

Using the reagent combination sodium azide/polyphosphoric acid, this one-pot, consecutive reaction of sodium azide and dicarbonyl compounds (II) with an aromatic compound (I) affords the quinolines (III) in low to moderate yields.

A complex reaction of vinyltrimethylsilane with triethylsilane catalyzed by ruthenium carbonyl and ruthenium phosphine complexes and performed at 80-130°C in air or oxygen-free conditions was followed by GC-MS. Catalytic examinations and identification of the products (I-X) allowed us to propose a general scheme for the competitive-consecutive reaction in which the complexes containing Ru-H and Ru-Si bonds play the role of key intermediates.

The consecutive reaction of phosphonium salt (1) with n -butyllithium, hexafluorobenzene or chloropentafluorobezene, halogen acyl halide and triethylamine gives pentafluorophenyl or chlorotetrafluorophenyl halogenoallenes in 63–93% yields.

2-Sulfonimidoylylidene tetrahydrofurans and 2-sulfonimidoylylidene-5-vinyl tetrahydrofurans were readily synthesized via a consecutive acylation/SN2 sequence with total regio- and chemoselectivity from Johnson's sulfoximine derivatives. The same consecutive reaction could also be applied to the expeditious synthesis of 6-sulfonimidoylmethyl-3,4-dihydro-2H-pyrans.

The consecutive reaction of diethyl (1‐cyanobut‐3‐enyl)phosphonate with n‐butyllithium, trifluoroacetic anhydride, and Grignard reagents gave trifluoromethylated 4‐cyano‐alka‐1,4‐dienes in 45–89% yields with predominant Z‐selectivity (Z∶E=89–78∶11∶22). Two isomers could be easily separated by column chromatography.

The consecutive reaction of phosphonates 1 with n-butyllithium, trifluoroacetic anhydride, and organozinc compounds gives trifluoromethylated α,β-unsaturated esters with an active methylene moiety and predominant Z-selectivity in 54–78% (3 steps) yields. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:289–292, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20018

The consecutive reaction of bis[2,2,2-trifluoroethyl]phosphite with sodium hydride, dimethyl maleate, and aldehydes gives 3-alkoxycarbonyl-β,γ-unsaturated esters with predominant Z-selectivity in 62–94% yields (Z/E = 85–60:15–40). The Z- and E-isomer can be separated conveniently by column chromatography. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:276–279, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10142

Consecutive reaction of 2-hydroxy-3-methoxybenzaldehyde (I) with allyl bromide (II) and ethyl azidoacetate (III) yields the unsaturated azido carboxylate (IV) which is converted into the carbodiimides (VIII) via the iminophosphoranes (VI).