N-Tritylprolinal (prepared in four steps from l-proline) shows a very high Felkin diastereoselectivity in its reaction with various nucleophiles, leading to a straightforward and highly stereoselective access to syn-proline-derived amino alcohols.

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A rapid and very precise method is proposed to simultaneously determine the position-specific 13 C content and the metabolomic profile of triacylglycerols (isotopomics). 13 C-NMR spectra are obtained by using an adiabatic INEPT sequence; the experiment time is reduced by a factor of 7 with respect to a one-pulse acquisition. † Electronic supplementary information (ESI) available: Details of 13 C-INEPT spectra acquisition and processing, pulse sequence scheme for adiabatic INEPT, designation of carbon atoms in triacylglycerol molecules, and enlargements of different regions in the 1 H and 13 C NMR spectra of olive oil for a resolving power comparison. See

A comparative study of the metallotropic equilibrium between 1-chloro-3-(trimethylsilyl)propargyl and -allenyl metals was undertaken by means of lithio-, titano-, and zinco-carbenoids. The lithium and zinc species were shown to react mainly in their allenic metallotropic forms, whereas the titanium species proved to react in both its propargylic and allenic forms. The configurational stability of these organometallics was next examined using a modification of the Hoffmann test. In each case, the organometallic was reacted with a chiral enantiopure electrophile. A comparison of the diastereomeric ratios obtained at low and high conversion rates of the reagent allows assessment of its configurational stability. The lithium species thus exhibited a configurational lability at −125 °C in Trapp mixture on the time scale of its reaction with (+)-camphor, while the titanium analogue proved to be configurationally stable at −40 °C in THF/Et 2 O on the time scale defined by its reaction with (S)-N-tritylprolinal. In the context of its reaction with the same electrophile, the zinc bromide species was proven to be partially labile from −80 °C in THF and its dynamic kinetic resolution was investigated.