Bioinspired Metal-Free Formal Decarbonylation of α-Branched Aliphatic Aldehydes at Ambient Temperature

A sequence of a Baeyer–Villiger oxidation and a Lewis acid-promoted reduction of the resulting formate with Et₃SiH enabled the metal-free formal decarbonylation of tertiary and secondary aliphatic aldehydes. The new methodology mimics the biosynthetic decarbonylation pathway through oxidative C−C bond cleavage rather than the C(O)−H bond activation known from conventional Tsuji–Wilkinson-type reactions. The substrate scope is complementary to existing transition-metal-catalyzed protocols.     

Electronic Absorption Spectra of Transient Boron-Sulphur Species in the Gas Phase

The vapour phase flash photolysis of boron triiodide, in the presence of carbon disulphide or carbon oxysulphide, produces two sets of spectral absorption bands centred near 412 and 625 nm, respectively. These are attributed to the previously unreported BS₂ radical. The lower states of the gamma emission band system of BS and the alpha and beta systems of BO are confirmed as the ground electronic states.     

The Modifiable Character of a Novel Ru-Fe-B/ZrO2 Catalyst for Benzene Selective Hydrogenation to Cyclohexene

A novel Ru‐Fe‐B/ZrO₂ catalyst for the selective hydrogenation of benzene to cyclohexene was prepared by the chemical reduction method. A yield of cyclohexene of 57.3% was achieved at benzene conversion of 80.6% on this catalyst. The activity and yield of cyclohexene were higher than those studied previously. The structural characterizations of the catalyst were performed by TEM‐SAED, XRD, and N₂‐physisorption. Moreover, cyclohexene selectivities on this catalyst increased and the activities decreased with the increase of the ZnO dosages, however, the activities increased and cyclohexene selectivities decreased with the increase of the H₂SO₄ dosages. Different feeding manners of H₂SO₄ or ZnO exerted definitely influence on the performances of this catalyst, but the degrees of influence were different due to the character of chemisorptions. Furthermore, the activity and cyclohexene selectivity on the catalysts could be reversibly modified by adding H₂SO₄ or ZnO into reaction slurry, which provides an easy method to recover the activity and selectivity of Ru‐Fe‐B/ZrO₂ catalysts during the process of producing cyclohexene. And the modifiable mechanisms involved were speculated.