Stereocontrolled elongation of a functionalized isoprene unit on the E or Z terminal methyl of terpenoids was achieved by the N-ylide rearrangement of the common ammonium salts under the selected reaction conditions. One of rearrangement products, all-(E)-sesquiterpene carboxylate was converted into β-sinensal, a component of the essential oil of Chinese orange. General aspects of these transformations were described.

Microstructural evolution during isothermal aging at temperatures ranging from 673 K to 773 K was investigated by transmission electron microscopy (TEM) for Ni-rich Ti-Zr-Ni alloys. It was revealed that the aging is a two-stage process: the first stage is characterized by circular diffuse scattering in electron diffraction patterns, most likely attributed to short range ordered structure with no significant microstructural change. Second stage is characterized by a fine coherent precipitation followed by the coarsening. The precipitates had a lenticular shape and their habit was f100g B2 . The electron diffraction pattern of the sample containing the precipitates exhibited satellite spots at 1=3h110i B2 and 1=4h210i B2 positions. High resolution TEM observations and fast Fourier transformation analysis revealed that the h100i B2 electron diffraction pattern was composed of the reflection from 4 variants of the precipitates. The two-stage microstructural evolutions coincide well with the previously reported changes in mechanical properties and martensitic transformation behavior.

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Effect of isothermal aging on martensitic transformation temperatures, mechanical properties and microstructure was investigated for a Ni-rich Ti-Zr-Ni shape memory alloy at temperatures ranging from 673 K to 773 K. The aging behaviour was two stage process: the first stage associated with an increase in the Vickers hardness and a decrease in martensitic transformation temperatures and the second stage with a decrease in the hardness and increase in the transformation temperatures. Second stage was also characterized by the appearance of nano-scale precipitates, which has never been reported.

Stereocontrolled elongation of a functionalized isoprene unit on the E or Z terminal methyl of terpenoids was achieved by N-ylide rearrangement of the common ammonium salts under selected reaction conditions. A 1,5-diene or conjugated triene skeleton can be furnished by reductive or oxidative removal of the amino group of the rearrangement product, respectively. As an application to natural-product synthesis, all-(E )-terpenoid (E )-11d and (E,Z)-terpenoid (Z )-11c were converted into β-sinensal and (13Z )-retinol, respectively. General aspects of these transformations and a plausible transition state for the N-ylide rearrangement are discussed.