Intermolecular carbon-carbon bond formation between acylsilanes and organoboronic esters was achieved by photoirradiation under almost neutral, transition metal-free conditions. In this reaction, siloxycarbenes generated by photoisomerization of acylsilanes reacted with boronic esters to give the formal B-C bond insertion intermediates, which underwent unique rearrangement to afford the cyclic R-alkoxyboronic esters. Acidic treatment of the resulting crude products under air furnished the crosscoupled ketones in good yields.

Phase behavior of silica-filled poly(dimethylsiloxane) (PDMS) network was investigated by wide-angle X-ray diffraction (WAXD) under various strain ratio between room temperature and -100°C, and anomalous polymorphic behavior was discovered. At room temperature, when sufficient strain was applied, PDMS network was found to transform into the mesomorphic phase from which only a pair of sharp equatorial reflections and faint meridional scattering were obtained in the WAXD pattern. At low temperature, PDMS network crystallized into one of three different crystal forms according to strain ratio. These crystal forms were denoted as , transient and forms in the descending order of corresponding strain ratio. The mesomorphic phase at room temperature transformed into the crystalline  form by reducing temperature. There was an anomalous feature about the transition of the crystalline forms that the position of reflections in the WAXD pattern changed continuously and reversibly with strain between the  and the  forms through the transient form, while keeping the diffraction angles almost unchanged.3

The [3+2] cycloaddition reaction of a tungsten-containing carbonyl ylide with methyl vinyl ether and the insertion reactions of the nonstabilized carbene complex intermediates produced have been investigated through the use of B3LYP density functional theory. The [3+2] cycloaddition reaction of the tungsten-containing carbonyl ylide has been proven to proceed concertedly, reversibly, and with high endo selectivity. The intermolecular Si-H insertion reactions of the carbene complex intermediates have been proven to be favored over the intramolecular C-H insertion, in good agreement with experimental results. Moreover, the kinetic endo/exo ratio of the [3+2] cycloaddition reaction has been shown to determine the endo/exo selectivity of the Si-H insertion products. In addition, secondary orbital interactions involving the benzene ring and the carbonyl ligand on the metal center have turned out to strongly influence the high endo selectivity of the [3+2] cycloaddition reaction with methyl vinyl ether.

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Durch Wasserstoffübertragung von N‐Benzylanilin in Gegenwart von Palladium‐Aktivkohle werden die Diphenylacetylene (I) selektiv zu den entsprechenden Stilbenen hydriert.