Electron scattering experiments have been performed on the deformed nuclei 5 Sm, Sm, Fr, 7 Yb Th, and U at momentum transfers between 0.5 fm and 1.3 fm l The cross sections for the 0, 2+, and 4+ rotational states of these nuclei have been obtained and, together with other information on the electromagnetic properties of these nuclei, these data lead to information about the deformed shapes. The shapes of '6~Er and '~Y b are quite different from the shapes of 5 Sm and 4Sm and require a varying skin thickness. The Sm isotopes require a constant skin thickness. Results are presented for po(r), p2(&), and p4(r).NUCLEAR REACTIONS~Sm(e, e') ls4Sm(e, e'), 6 Er(e, e') Yb(e, e') Th( e, e'), and~U(e, e'); measured cross sections for ground state and first excited states for 0.5 «q eff~1 .2 fm

A new asymmetric synthesis of alpha-amino acids is described in which the key step is the highly diastereoselective addition of organolithium carboxyl synthons (2-furyllithium, phenyllithium, vinyllithium) to (R)- and (S)-O-(1-phenylbutyl) oximes to give hydroxylamines, with vinyllithium being the most satisfactory nucleophilic reagent. Subsequent reductive cleavage of the N-O bond in hydroxylamines, followed by N-protection, and oxidative cleavage of the carboxyl precursor gave a range of N-protected amino acids and esters. The method was exemplified by the synthesis of a range of derivatives of non-proteinogenic amino acids such as 4-bromophenylalanine, tert-leucine, norvaline, cyclohexyl- and aryl-glycines, 2-amino-8-oxodecanoic acid (Aoda) and alpha-methylvaline.

Addition of a range of organolithium and Grignard reagents to (E)-O-(1-phenylbutyl)benzyloxyacetaldoxime 1 in the presence of boron trifluoride diethyl etherate is highly diastereoselective. The resulting hydroxylamines undergo N-O bond cleavage upon treatment with zinc-acetic acid or molybdenum hexacarbonyl to give, after N-protection, protected 1,2-aminoalcohols 3 in high enantiomeric purity. Debenzylation of 3a and 3d gave N-Boc (R)-alaninol and (S)-phenylalaninol respectively. The hydroxylamines 2 also serve as alpha-amino acid precursors, 2i being converted into N-formyl-(R)-alaninyl-(S)-(4-bromo)phenylalanine ester 7, the N-terminal dipeptide of a natural depsipeptide. The versatility of the 1,2-aminoalcohol derivatives was further illustrated by their conversion into 5-, 6- and 7-membered 2-hydroxymethyl nitrogen heterocycles 15-19 in high enantiomeric excess by a ring-closing metathesis reaction. Further reaction of the dihydropyrrole 15 gave the iminosugar 1,4-dideoxy-1,4-imino-D-ribitol.

We have measured the cross sections for excitation of the ground-state rotational band in *^^Sm by high-energy electrons. The ground-state charge distribution has been determined including the deformation parameters j Sg and /S^ of the nuclear surface.

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