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The glycerol has been identified as a main platform product in biorefineries and its use as a renewable raw material has gained the great attention of the scientific community. Thanks to its unique structure, bioavailability, properties and renewability, scientists consider glycerol as a non-toxic bio-sourced building block for chemical transformations into higher added-value substances, meeting the objectives of minimizing the environmental impact and economic risk and giving a value to the production of biodiesel. In this chapter, we highlighted the important progress by summarizing; the representative achievements for the different promising reactions focusing on glycerol valorization and reactional mechanisms proposed for some processes.

Boron chemistry has evolved to become one of the most diverse and applied fields in organic synthesis and catalysis. Various valuable reactions such as hydroborylations and Suzuki−Miyaura cross-couplings (SMCs) are now considered as indispensable methods in the synthetic toolbox of researchers in academia and industry. The development of novel sterically- and electronically-demanding C(sp3)−Boron reagents and their subsequent metal-catalyzed cross-couplings attracts strong attention and serves in turn to expedite the wheel of innovative applications of otherwise challenging organic adducts in different fields. This review describes the significant progress in the utilization of classical and novel C(sp3)−B reagents (9-BBN and 9-MeO-9-BBN, trifluoroboronates, alkylboranes, alkylboronic acids, MIDA, etc.) as coupling partners in challenging metal-catalyzed C(sp3)−C(sp2) cross-coupling reactions, such as B-alkyl SMCs after 2001.

A new and mild method of glycerol acetalization reaction with various carbonyl compounds catalyzed by the cheap and simple iron catalyst FeCl3·6H2O has been developed. This method which consists in the transformation of glycerol to cyclic acetals under mild conditions, with or without solvent, allowed interesting results: glycerol acetalization using ketones leads to the corresponding 1,3-dioxolanes with a very good selectivity (97–100%), whereas mixture of 1,3-dioxolanes and 1,3-dioxanes was formed when using aldehydes, with a good selectivity toward 1,3-dioxanes up to 76%.

Three novel symmetrical ferrocenyl diphosphines with tertiary phosphorus atoms holding respectively nitrogen-containing heterocyclic derivatives of pyrrole, imidazole and benzazaphosphole were synthesized and characterized. Up to now, integration of heteroaromatic fragments, or more generally hetero-cycles, as substituents on the tertiary phosphines of symmetrical ferrocenyl diphosphines has been limited to the furyl motif. Their coordination to palladium and platinum group 10 transition metals was exemplified, and analyzed using single crystal X-ray diffraction. The performances obtained in palladium-catalyzed copper-free Sonogashira and Suzuki cross-coupling reactions using bromoarenes and chloroarenes are reported for the most efficient system. The unprecedented combination of a tert -butyl group and of an imidazolyl motif on the phosphorus atoms led to an air-stable ferrocenyl diphosphine, which allowed in combination with 0.1–0.2 mol% of palladium to generate catalytic systems able to couple some activated chloroarenes and most of the bromoarenes examined.

The synthesis of new 6-LB10H13 (L = ligand) derivatives of decaborane B10H14 with different ligands was achieved by the opening cage reaction of closo-decahydrodecaborate (NH4)2B10H10 in the presence of a strong acid (HNO3 or H2SO4) in organic solvents (hexane or benzene derivatives). This reaction was performed by varying different factors: the acid strength, the solvent polarity, the equivalent amounts of (NH4)2B10H10 with respect to the acid used (1/4 or 1/6) and the reaction time (30 minutes to 24 hours). Nitric acid forced hexane solvent to play the role of ligand whereas sulfuric acid did not. The reaction of (NH4)2B10H10 with HNO3 in hexane produced 6-(C6H13)B10H13 and [B9H13NO3]−. The reaction of (NH4)2B10H10 with H2SO4 in aromatic solvent L (benzene, toluene, o-xylene and m-xylene) produced 6-LB10H13 and 6-(HO3SO)B10H13 as major products with B6H10 and [B9H14]− as minor products. All these derivatives were characterized by 11B NMR, 1H NMR, 13C NMR and negative ESI. This study elucidated some facts and ideas that were not clear concerning the mechanism of opening reaction of closo-[B10H10]2−.

SSCI-VIDE+CDFA+QLE:IKA:CPI:LDJ:FRA; International audience; This Letter describes novel families of terpene derivatives bearing amino and alcohol functions, synthetically obtained through thetelomerization of ethanolamine with isoprene. This reaction wasperformed at 90 degrees C in methanol and catalyzed by a Pd/PPh3 system.Four different product families were obtained depending on thetelomerization degree with a total yield upto 85%. Monotelomers andditelomers have been found to form preferentially. A variation ofreagent stoichiometry allowed the tuning of the mono-telomer andditelomer selectivities within a 50-80% and 20-50% range, respectively.The best compromise total yield/monotelomer selectivity was obtainedwith 2 equiv of isoprene per ethanolamine. Deep analysis by NMRspectroscopy indicated that the monotelomer family was composed of 6isomers, the main isomer possessing a tail-to-head trans configurationwith a selectivity of 32.5% among all monotelomers. (C) 2015 ElsevierLtd. All rights reserved.

Ethyl 2-(N-methylformate-1,4,5,6-tetrahydropyridin-2-yl) acetate with endocyclic double bond was prepared with high regioselectivity and further reduced into (R)-N-protected homopipecolate with a good enantioselectivity using chiral ruthenium catalyst.

The synthesis of a fluorene derivative bearing a fluorescein moiety is described together with its anodic electropolymerization in presence of various amount of fluorene. Both polymers and monomers can be used as pH indicators in water and other medium. The fluorescence and absorption properties in function of the pH are presented and compared with those of fluorescein. In the excited state, the Fluorescein–fluorene monomer appears to be a stronger acid than fluorescein.

Heteropoly compounds provide a good basis in acid-base and redox catalysis. In particular, heteropoly acids (HPA) catalyse a wide variety of reactions offering strong options for more efficient and cleaner processes compared to classical inorganic acids. They are more efficient than conventional catalysts, such as silica-alumina, zeolites, etc.. Because of their low surface areas (1-10m 2 /g), heteropoly acids are usually supported for catalytic applications. Amorphous silica or all-silica mesoporous molecular sieves are often used as supports for HPA's These catalysts are usually prepared by the wetness impregnation method. The chief disadvantage of this method is the leaching of the active phase when the catalyst is employed in liquid phase reactions. Our study consisted in the direct incorporation of tungstophosphate species (HPW) into the walls of mesoporous silica. Subsequently, the catalytic activity of a highly-incorporated HPW-MCM-41 material was tested in the epoxidation of cyclohexene using H 2 O 2 as oxidant. On the basis of the experimental results, the samples show a good cyclohexene conversion rate; five main products were detected, i.e. epoxide, cyclohexanediol, 2-cyclohexene-1-ol or 3-cyclohexene-1-ol, cyclohexanone-2-hydroxy, and 2-cyclohexene-1,4-diol. The epoxide formed during the reaction seems to undergo further hydrolysis into cyclohexanediol. This could be do to the acidic nature of the catalysts.

The title compound (III) can be used as a precursor of β-amino acids and as an intermediate in organic syntheses.

A friendly method for the protection of diols and carbonyls catalysed by hexahydrated iron (III) chloride has been developed. This method, which consists of the transformation of diols and carbonyls to cyclic acetals, functions in mild conditions and it is efficient for a wide range of diols.

Several 1-zirconaindenes ( 4 ) have been obtained easily by heating phenylmethylzirconocene with various symmetrical (R  R′  CH 3 , C 2 H 5 , n-C 3 H 7 , Si(CH 3 ) 3 and unsymmetrical (R  CH 3 , R′  Si(CH 3 ) 3 ) alkynes (RCCR′). Under similar experimental conditions, the ynamine, diethylaminotrimethylsilylethyne, led to a regioselective reaction. From the X-ray structure of the zirconaindene product, the trimethylsilyl group was found close to the zirconium atom. Compounds 4 with germanium tetrachloride afford new 1-germaindenes ( 7 ) characterized by 1 H and 13 C NMR and mass spectrometry, in good yield.