1,5-hydride shift of alkenyl sulfoximine/[4+3] cycloaddition and ring opening/novel hydrazine synthesis from Tröger's base analogues
Metadata[+] Show full item record
Three synthetic methodologies are studied in details in this dissertation. For 1,5-hydride shift of alkenyl sulfoximine methodology, the reaction mechanism was studied using deuterium labeling. An uncommon 6-endo-trig 1,5-hydride shift process was discovered. The scope and limitation were studied using N-alkyl, N-allyl, and N-benzyl-substituted S-alkenyl sulfoximines. N-H-S-alkyl sulfoximines, four- and six-membered heterocyclic rings and a new class of chiral dienes were obtained. In [4+3] cycloaddition and ring opening chapter, we demonstrated an ene-like reaction using a symmetric oxyallylic cation can provide α-substituted cyclopentenones. Enantio pure products are potentially accessible by this method. [4+3] Cycloaddition of the symmetric oxyallylic cation with substituted furans, and the ring-opening process of the resulting 8-oxabicyclo[3.2.1]oct-6-en-3-one were also studied. The reaction conditions and scope were investigated. An acid-catalyzed mechanism was proposed for the ring-opening process. In the third chapter, we showed some interesting tetracyclic hydrazine compounds can be synthesized from Tröger's base analogues 1 by using the Polonovski reaction conditions. An oxidative rearrangement mechanism was proposed. Products were not obtained from some steric hindered Tröger's base analogues.