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An efficient palladium-catalyzed C–H bond alkenylation/annulation strategy to access carboline carboxylates from indolyl ketoximes and acrylates through C–C/C–N bond formation is reported. Indolyl ketoximes not only direct ortho-olefination with acrylates, but also undergo an intramolecular N–O bond cleavage/traceless annulation to construct carboline carboxylates straightforwardly in this concise method.

A palladium-catalyzed Csp3–H bond mono-aroyloxylation of O-alkyl substituted oxime ethers has been developed by using 2,4,6-trimethoxybenzaldoxime as an exo-type directing group with exclusive site-selectivity. With the wide range of masked aliphatic alcohol substrates and aromatic acid coupling partners, the protocol allows rapid access to various 2-alkyl substituted glycol derivatives in synthetically useful to good yields. The employed directing group is readily removed, accordingly affording valuable functionalized aliphatic alcohols. When the solvent from hybrid DCE/HFIP to CH3CN, non-directed oxidative cross-coupling is observed between the electron-rich aromatic ring of substrates and aromatic acid partners.

A novel one-pot, three-component Wittig–S N Ar approach to ethyl ( E )-3-[4-(morpholino-1-yl)-3-nitrophenyl]acrylate, ethyl ( E )-3-[3-cyano-4-(morpholino-1-yl)phenyl]acrylates, ethyl ( E )-3-[2-(morpholino-1-yl)-5-nitrophenyl]acrylate, ethyl ( E )-3-[5-(morpholino-1-yl)-4-nirtofuryl-2-yl]acrylates, and their analogues, which would be used as intermediates of aurora 2 kinase inhibitors ,etc. has been developed starting from readily available nitro- or cyano-group-activated haloaromatic aldehydes, secondary amines, quaternary phosphonium salts, and sodium hydroxide, using water as a solvent, with high stereoselectivity and in moderate to high yield. The noteworthy features of this one-pot, three-component process is highlighted by its rapid and highly efficient formation of a new C(sp 2 )–N bond and a new C(sp 2 )–C(sp 2 ) double bond using water as a simple nontoxic convenient and environmentally benign solvent under metal-free mild reaction conditions.

An one-pot stereoselective synthesis of 2-aminobenzylidene derivatives from readily available 5-nitro/cyano-activated 2-halobenzaldehydes (2-chloro-5-nitrobenzaldehyde, 2-bromo-5-nitrobenzaldehyde, 2-fluoro-5-nitrobenzaldehyde, 5-cyano-2-fluorobenzaldehyde), the active methylidene compounds (cyanoacetamide and ethyl cyanoacetate), and secondary cycloamines via a novel parallel convergent Knoevenagel–nucleophilic aromatic substitution and nucleophilic aromatic substitution–Knoevenagel condensation cascade approach under mild conditions has been developed with high stereoselectivity and in 52–88% yields.

A stereoselective or exclusive approach to a series of ethyl (Z)-2-(2-substituted-thiazol-4-yl)pent-2-enoates from ethyl (E/Z)-2-(2-bromoacetyl)pent-2-enoate and thioureas or thioamides was reported in good yields. This approach involves a quaternary carbon stereocontrolled cis-configuration formation, and opportunely blocking a potential E/Z isomerization. The practical applicability was highlighted by the synthesis of (Z)-2-(2-tert-butoxycarbonylaminothiazol-4-yl)pent-2-enoic acid, a commercially important side-chain material of cefcapene pivoxil, in a two-step procedure.