I-O. AziridinesI. Basic PrinciplesSahebi, M.; Wipf, P.; Heimgartner, H., "3-Amino-2H-azirines in thesynthesis of peptides: tetrapeptides with α,α-disubstituted α-aminoacids." Tetrahedron 1989, 45, 2999-3010.HNXONOHXSHONHONSO NNHONONHONNXOHOXHNONODr. P. WipfPage 1 of 53/24/2008Wipf, P.; Venkatraman, S.; Miller, C. P., "A new synthesis of α-methylserine by nucleophilic ring-opening of N-sulfonyl aziridines."Tetrahedron Lett. 1995, 36, 3639.OOHOOTrNHOTrHNOTrOBnSesHNOHOBnSesH2NOHOHOO1. TBAF (4 eq), dioxane, 110 °C, 12 h 2. H2, Pd(OH)2, MeOH, HCO2H, 1 h3. 1.5 M NH3, AG-Wx8 Dowex ion exchange chromatography, 50%2. Ph3P, CH3CN, 83 °C, 30 min60-75%TrCl, Et3N, DMAPCH2Cl2, 72-85%1. NaN3, NH4Cl, MeOH, 64 °C, 4 h2. BnOH (3 eq), NaH (3 eq), dioxane, 90 °C, 3 h89-95%1. Ses-Cl, Et3N, CH2Cl2 0 °C, 1 h3. NaClO2, iso-butene, NaH2PO4, THF, H2O, 2 h, 90%1. TsOH, MeOH, 15 h 2. Py.SO3, DMSO, Et3N, CH2Cl2, 3 h, 86%SSDr. P. WipfPage 2 of 53/24/2008Gabriel-Cromwell Reaction- Filigheddu, S. N.; Taddei, M. Tetrahedron Lett. 1998, 39, 3857.Alkene Aziridination- Tian, X.; Hudlicky, T.; Königsberger, K. J. Am. Chem. Soc. 1995,117, 3643.Aziridines by formation of a,b-bondsR CO2R'NH2+CO2R'BrEt3NRCO2R'NCO2R'BrOHOHBrOOTsN1. DMP, TsOH, CH2Cl22. PhI=NTs, Cu(acac)2 MeCNDr. P. WipfPage 3 of 53/24/20081,3-Dipolar Cycloaddition of Azomethine Ylides- Vedejs, E.; Klapars, A.; Naidu, B. N.; Piotrowski, D. W.; Tucci, F. C., "Enantiocontrolled synthesis of (1S,2S)-6-desmethyl-(methylaziridino)mitosene." J. Am. Chem. Soc. 20 00, 122, 5401-5402.NOTBSOBH3H OONHTrNOTBSONTrOC3H5NOTBSOOHNHTrOC3H5NOTBSONMeOC3H51. BuLi2. 3. AcOH, EtOH93%DEAD, Ph3P71%1. Me3NBH3, TFA2. BuLi; MeI1. [Cp2Zr]2. PPh3, DEAD, MeI6 : 170%82%Dr. P. WipfPage 4 of 53/24/2008NOTBSONMeINONMeCNHNNMeCNOOAcC!CCH2OTBSHONONMeOTBSONONMeOONHFmocNONMeIC!CCH2OTBSOAcONOAcNMeOTBSONONMeOONH21. HF/Py, MeCN2. Dess-Martin Ox.3. LiC!CCH2OTBS4. DMAP, Ac2O60%1. AgOTf, CD3CN 70 °C2. BnMe3NCN, MeCN40%1. O2, DABCO Co(II)salen2. HF/Py3. Fmoc-N=C=O TEA1. NaOH, MeOH2. TPAP, NMO59%55%TEA, CH2Cl281%Dr. P. WipfPage 5 of
View Full Document
Unlocking...