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The focus of this thesis work is the asymmetric synthesis of N,O-protected 1,3-aminoalcohols using SAMP/RAMP Hydrazones and their application in asymmetric synthesis. Furthermore, the asymmetric synthesis of 2-substituted azetidines was developed. - Asymmetric synthesis of 1,3-aminoalcoholsA flexible diastereo- and enantioselective synthesis of N,O-protected 1,3-aminoalcohols was developed. In a three step synthesis, first the N,O-protected 1,3-aminoalcohols were synthesized using a nucleophilic 1,2-addition to the C=N-double bond of the SAMP/RAMP hydrazones with organolithium- or organocer-reagents. Second, an epimerization-free reductive N,N-bond-claverage with BH3-THF-complex was performed. Lastly, N-protection with chloroformic acid benzyl ester or tosylchloride afforded the benzylcarbamates or tosylamides, respectively, in overall yields of 22 to 69%. Importantly, the products were formed in high enantio- and diastereomeric purities (ee, de >= 89–96%). - Synthesis of 2-substituted azetidines using activated leaving groups Extending the previous work of J.H. Kirchhoff, 2-substituted azetidines were synthesized using activated leaving group. The 1,3-aminoalcohols, whose amine and alcohol groups were benzylcarbamate and silyl protected, respectively, were first de-silylated. Conversion of the free alcohol to iodide or tosylate afforded the azetidine precursors. Cyclization gave the desired 2-substituted azetidines in 38 to 50% yields over three steps in excellent enantiomeric purities (ee >= 96%). - Synthesis of 2-substituted azetidines under Mitsunobu conditions The 1,3-aminoalcohols, whose amine and alcohol groups were p-tosyl and benzyl protected, respectively, were first de-benzylated with palladium on activated charcoal in methanol. Then, cyclization was effected by treatment with triphenylphosphine and DIAD in THF. The desired 2-substituted azetidines were obtained in 73 to 93% yields over two steps and in excellent enantiomeric excesses (ee >= 96%). Notably, a variety of substituents could be incorporated (n-Bu, t-Bu, n Hexyl, Phenyl, TBSOCH2(CH2)nCH2, n = 1, 2, 3).

The Große Heidelberger Liederhandschrift (Univ.-Bibl. Heidelberg cpg 848; or Codex Manesse), is probably the most important collection of medieval vernacular lyric from its beginnings until around 1300. It contains approximately 5240 stanzas and 36 lais representing 140 poets. The process of its compilation which lasted several decades is the subject of this dissertation. In the first part the manuscript’s emergence is traced in detail. On the basis of this investigation chronologically delimited segments within the Codex can be determined. In the second part these segments are examined as to how their texts have been passed on especially in comparison to the transmission of these texts in the Weingartner and the Kleine Heidelberger Liederhandschrift. The oldest inventory of the Codex Manesse exhibits already a conspicuous tendency of pure rhyme and formal-metrical assimilation of the stanzas of a “Ton”. This tendency proves to be an underlying principal. Therefore, it is shown that the Codex Manesse is compiled with recognizable principles. The paper concludes with a discussion of the possible consequences for the interpretation and editing of medieval lyric.