{"id":{"repo_id":"glasgow","oai_identifier":"oai:theses.gla.ac.uk:730"},"canonical_url":"https://search.dev.ndltd.org/etd/glasgow/oai:theses.gla.ac.uk:730","repository":{"repo_id":"glasgow","name":"University of Glasgow","base_url":"https://theses.gla.ac.uk/cgi/oai2"},"display":{"title":"Novel titanium carbenoid reagents: diversity orientated synthesis of indoles and spirocycles","abstract":"A new synthetic strategy for the preparation of a 96-member library of 2,5-disubstituted indoles involving traceless cleavage from resin is presented. A boronate-bearing titanium alkylidene was prepared and used to convert 8 resin-bound esters into immobilised enol ethers. Cleavage from resin in mild acid with concomitant cyclisation yielded boronate-bearing indoles. Capitalising on the immobilised boronate functionality in enol ethers, Suzuki cross-coupling reactions were performed with 12 aryl iodides to give a 96-member library after cleavage from resin with mild acid. 79 members of the library were confirmed to be 2,5-disubstituted indoles. Also reported is the use of tertiary butyllithium and 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane to convert an aryl bromide into an arylboronate in the presence of a dithiane, with simultaneous reduction of an aryl azide to an amine. In a similar route, we synthesised dithiane for the attempted conversion of resin-bound esters into functionalised 7-azaindoles after cleavage from resin. Further investigation with a different ortho-nitrogen protecting group may yet prove successful. Alkylidenation of lactones with functionalized titanium carbenoid reagents followed by acid-induced cyclisation of the resulting enol ethers constitutes a new method for the preparation of [4.4], [4.5], and [5.5] spiroacetals (1,6-dioxaspiro[4.4]nonanes, 1,6-dioxaspiro[4.5]decanes and 1,7-dioxaspiro[5.5]undecanes). The titanium carbenoids are easily generated from readily available thioacetals.","abstract_html":"A new synthetic strategy for the preparation of a 96-member library of 2,5-disubstituted indoles involving traceless cleavage from resin is presented. A boronate-bearing titanium alkylidene was prepared and used to convert 8 resin-bound esters into immobilised enol ethers. Cleavage from resin in mild acid with concomitant cyclisation yielded boronate-bearing indoles. Capitalising on the immobilised boronate functionality in enol ethers, Suzuki cross-coupling reactions were performed with 12 aryl iodides to give a 96-member library after cleavage from resin with mild acid. 79 members of the library were confirmed to be 2,5-disubstituted indoles. Also reported is the use of tertiary butyllithium and 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane to convert an aryl bromide into an arylboronate in the presence of a dithiane, with simultaneous reduction of an aryl azide to an amine. In a similar route, we synthesised dithiane for the attempted conversion of resin-bound esters into functionalised 7-azaindoles after cleavage from resin. Further investigation with a different ortho-nitrogen protecting group may yet prove successful. Alkylidenation of lactones with functionalized titanium carbenoid reagents followed by acid-induced cyclisation of the resulting enol ethers constitutes a new method for the preparation of [4.4], [4.5], and [5.5] spiroacetals (1,6-dioxaspiro[4.4]nonanes, 1,6-dioxaspiro[4.5]decanes and 1,7-dioxaspiro[5.5]undecanes). The titanium carbenoids are easily generated from readily available thioacetals.","abstract_has_math":false,"creators":["Main, Calver A."],"institution":"University of Glasgow","degree_name":null,"degree_level":"PhD","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2008,"date_issued":"2008","date_published":"2008","updated_at":"2026-07-24T02:23:30Z","subjects":["QD Chemistry"],"languages":["en"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Main, Calver A."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2008"]},{"key":"dc:date.issued","label":"Date","values":["2008"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Glasgow"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["https://theses.gla.ac.uk/730/"]},{"key":"dc:relation.isreferencedby.uri","label":"Dc Relation Isreferencedby URI","values":["https://gla.on.worldcat.org/oclc/1547483784"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["PhD"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["QD Chemistry"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://theses.gla.ac.uk/730/1/ThesisCS.pdf","https://theses.gla.ac.uk/730/2/2008mainphd.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["A new synthetic strategy for the preparation of a 96-member library of 2,5-disubstituted indoles involving traceless cleavage from resin is presented. A boronate-bearing titanium alkylidene was prepared and used to convert 8 resin-bound esters into immobilised enol ethers. Cleavage from resin in mild acid with concomitant cyclisation yielded boronate-bearing indoles. Capitalising on the immobilised boronate functionality in enol ethers, Suzuki cross-coupling reactions were performed with 12 aryl iodides to give a 96-member library after cleavage from resin with mild acid. 79 members of the library were confirmed to be 2,5-disubstituted indoles. Also reported is the use of tertiary butyllithium and 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane to convert an aryl bromide into an arylboronate in the presence of a dithiane, with simultaneous reduction of an aryl azide to an amine. In a similar route, we synthesised dithiane for the attempted conversion of resin-bound esters into functionalised 7-azaindoles after cleavage from resin. Further investigation with a different ortho-nitrogen protecting group may yet prove successful. Alkylidenation of lactones with functionalized titanium carbenoid reagents followed by acid-induced cyclisation of the resulting enol ethers constitutes a new method for the preparation of [4.4], [4.5], and [5.5] spiroacetals (1,6-dioxaspiro[4.4]nonanes, 1,6-dioxaspiro[4.5]decanes and 1,7-dioxaspiro[5.5]undecanes). The titanium carbenoids are easily generated from readily available thioacetals."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Novel titanium carbenoid reagents: diversity orientated synthesis of indoles and spirocycles"]}]}],"canonical_facts":{"dc:creator":["Main, Calver A."],"dc:date":["2008"],"dc:date.issued":["2008"],"dc:description.abstract":["A new synthetic strategy for the preparation of a 96-member library of 2,5-disubstituted indoles involving traceless cleavage from resin is presented. A boronate-bearing titanium alkylidene was prepared and used to convert 8 resin-bound esters into immobilised enol ethers. Cleavage from resin in mild acid with concomitant cyclisation yielded boronate-bearing indoles. Capitalising on the immobilised boronate functionality in enol ethers, Suzuki cross-coupling reactions were performed with 12 aryl iodides to give a 96-member library after cleavage from resin with mild acid. 79 members of the library were confirmed to be 2,5-disubstituted indoles. Also reported is the use of tertiary butyllithium and 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane to convert an aryl bromide into an arylboronate in the presence of a dithiane, with simultaneous reduction of an aryl azide to an amine. In a similar route, we synthesised dithiane for the attempted conversion of resin-bound esters into functionalised 7-azaindoles after cleavage from resin. Further investigation with a different ortho-nitrogen protecting group may yet prove successful. Alkylidenation of lactones with functionalized titanium carbenoid reagents followed by acid-induced cyclisation of the resulting enol ethers constitutes a new method for the preparation of [4.4], [4.5], and [5.5] spiroacetals (1,6-dioxaspiro[4.4]nonanes, 1,6-dioxaspiro[4.5]decanes and 1,7-dioxaspiro[5.5]undecanes). The titanium carbenoids are easily generated from readily available thioacetals."],"dc:format":["application/pdf"],"dc:identifier.uri":["https://theses.gla.ac.uk/730/1/ThesisCS.pdf","https://theses.gla.ac.uk/730/2/2008mainphd.pdf"],"dc:language":["en"],"dc:publisher.institution":["University of Glasgow"],"dc:relation.isreferencedby":["https://theses.gla.ac.uk/730/"],"dc:relation.isreferencedby.uri":["https://gla.on.worldcat.org/oclc/1547483784"],"dc:subject":["QD Chemistry"],"dc:title":["Novel titanium carbenoid reagents: diversity orientated synthesis of indoles and spirocycles"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["PhD"]},"updated_at":"2026-07-24T02:23:30Z"}