Stereoselective Synthesis of (E)-α,β-Dehydroamino Acid Esters. -The presented method gives access to the E-isomers of α,β-dehydroamino acid esters in high yields and is complementary to the existing methods for the preparation of the thermodynamically more stable Z-isomers. The E/Z ratio depends on the reaction conditions as well as on the substituents and protecting groups on the substrates. The best results are obtained by using NaI as additive for aryl-substituted substrates and MgBr 2 ·Et 2 O or ZnCl2 for alkyl-substituted substrates. -(YASUMO, Y.; HAMADA, M.; YAMADA, T.; SHINADA, T.; OHFUNE*, Y.; Eur.

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Aging wiring in buildings, aircraft and transportation systems, consumer products, industrial machinery, etc. is among the most significant potential causes of catastrophic failure and maintenance cost in these structures. Smart wire health monitoring can therefore have a ,u["tautial impact on the overall health monitoring of the system. Rdlectometry is commonly used for locating faults on wire and cables. This paper compares Time domain reflectometry (TDR), trequency domain reflectometry (FOR), mixed signal retlectometry (MSR), sequence time domain rel1eetometry (STDR), spread spectrum time domain rcflcctometry (SSTDR) and capacitance sensors in terms of their accuracy, convenience, cost, size, and ease of use. Advantages and limitations of each method are outlined and evaluated for several types of aircraft cables. The results in this paper can be extrapolated to other types of wire and cnhl~

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