A general method for the formation of acetals using chlorotrimethylsilane has been developed. Dioxolanes are formed from most carbonyl groups whereas methyl acetals are only formed from electron-poor carbonyl groups. The intermediacy of a silicon-bound carbonyl species is discussed. / The method has been extended to the formation of esters. In a solution of the alcohol to be esterified, methyl, ethyl, benzyl and 2-trimethylsilylethyl esters are readily formed in the presence of chlorotrimethylsilane. Using ('29)Si-N.M.R., a trimethylsilyl ester has been shown to be an intermediate in the reaction. / The Lewis acid catalyzed condensation of 1,3-bis-trimethylsiloxy-1-methoxy-1,3-butadiene with a variety of dielectrophiles, in a 1,2 relationship, has been investigated. The relative order of electrophilic reactivity towards this compound has been found to be; RR'C(Cl)SC(,6)H(,5) > ArCOCHO > ArCOCHO > RC(OCH(,3))(,2),RC(OCH(,3))SC(,6)H(,5) > RCHCl(,2). The dialkylation of 1,3-bis-trimethylsiloxy-1-methoxy-1,3-butadiene has been shown to lead to hydroxycyclopentenones with the same substitution pattern as the prostaglandins skeleton. Using ('29)Si-N.M.R., the mechanism of this reaction has been shown to proceed in two sequential steps; reaction of the (gamma)-position takes place first to give a titanium-bound intermediate, the thus formed intermediate then undergoes (alpha)-alkylation to give the cyclopentenone compound.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.71880 |
| Date | January 1983 |
| Creators | Brook, Michael Adrian. |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Chemistry.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 000194982, proquestno: AAINK66616, Theses scanned by UMI/ProQuest. |
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