A facile and efficient self-sorting assemble (CSA) strategy has been paved for bottom-up construction of the 3-fold symmetrical and highly substituted hexa-cata-hexabenzocoronenes (c-HBCs), the trithieno analogues, and larger disc-shaped PAHs from simple chemicals using benzylic carbons as tenon joints and a novel FeCl3-mediated AAA process as a key step. The structures of the as-prepared c-HBCs and related NGs were clearly identified by spectral analyses and X-ray crystallographic studies. Moreover, these can be envisaged to serve as new launching platforms for the construction of larger and more complex π-conjugated molecules and supramolecular architectures because of the modifiable and symmetrical decorations.

A unique domino reaction of enolizable carbonyl compounds with Me3SiCF2Br to construct α-fluoroenones and α-fluoroenals is described to undergo the in situ formation of difluorocarbene and silyl enol ether, difluorocyclopropanation, desilylation, ring-opening, and defluorination sequence. In this tandem reaction, Me3SiCF2Br acts as not only the difluorocarbene source but also the TMS transfer agent as well as internal bromide and fluoride anion catalyst. It allows the transformations to occur smoothly under only a catalytic amount of n-Bu4NBr as initiator.

A complete self-assistance strategy based on MeSiCFBr was used in the domino conversion of methylvinylketones into α,α-difluorinated cyclopentanones. Initiated by 5 mol % of nBuNBr, the multistep reaction occurred in one pot under mild conditions via the in situ formation of silyl dienol ethers, difluorocyclopropanation, thermal vinylcyclopropane-cyclopentene rearrangement, and desilylation. The process takes advantage of the multitasking capability of MeSiCFBr as the difluorocarbene source, a silicon-based transfer agent, and a bromine anion releaser.

A direct method for the synthesis of o-fluoronaphthols and o/p-fluorophenols has been developed by a catalytic ring expansion of indanones and 2-cyclopentenones, in which TMSCF2Br was used as a unique :CF2 source, a TMS transfer agent, as well as the Br(-) and F(-) releaser for the enolization, difluorocyclopropanation, desilylation, ring opening, defluorination, and aromatization sequence.

Three kinds of bio-oil-phenol-formaldehyde (BPF) resins were prepared which contained 30 wt% replacement of phenol with bio-oil derived from poplar, larch and bamboo. Main component of different pyrolysis bio-oil, physical properties of different BPF resins and their plywood specimens were investigated. The results show that phenolics in bio-oil derived from poplar, larch and bamboo are 13.8653%, 14.7529% and 10.3987%. All the experimental BPF resins have similar physical properties, which comply with GB/T 14732-2006. The performance of the plywood specimens bonded with different BPF resins were larch-BPF > poplar-BPF > bamboo-BPF, all of which could achieve the demands of GB/T 9846-2004.

No abstract

Unique imidoylation of thioorganics with isocyanides endows an unprecedented aerobic oxidation process. Catalyzed by Pd(Ph3P)2Cl2 in the presence of Ph3SiH under N2 then upon exposure to air, a wide range of α-acyl ketene dithioacetals react with isocyanides to afford 5-hydroxy-α,β-unsaturated γ-lactams via a C-S bond activation, isocyanide migratory insertion, hydrogenation, selective aerobic oxidation, and intramolecular nucleophilic addition sequence.

A combination of palladium and silane has been well used for the catalytic desulfurative cross‐coupling reactions under neutral conditions. Catalyzed by 10 mol‐% of bis(triphenylphosphine) palladium(II) dichloride in dimethylformamide in the presence of 2 equiv. of triphenylsilane, the carbocyclizations of α‐(3‐butenoyl) ketene dithioacetals took place smoothly leading to 2‐cyclopentenones in high yields. Thus, a new Heck‐type cyclization based on C–S bond cleavage for the synthesis of spiro compounds by using silanes as the desulfurative agents has been established.