Catalyzed Coupling of Organostannanes with Electrophiles
{'Code': '03090003', 'Directorate': {'Abbreviation': 'MPS', 'LongName': 'Direct For Mathematical & Physical Scien'}, 'Division': {'Abbreviation': 'CHE', 'LongName': 'Division Of Chemistry'}}
{'SignBlockName': 'George M. Rubottom'}
The synthesis of complex molecules requires the development of                  sensitive, cost-effective new reagents. This grant in the Organic               and Macromolecular Chemistry Program supports research leading to               new catalytic processes that will facilitate synthesis of  the                  new generation of antibiotics that are characterized by extremely               complex stereochemical interrelationships.                                                                                                                      It is the object of this research to explore synthetically useful               palladium-catalyzed coupling reactions utilizing an organotin                   reagent and an organic electrophile as coupling partners.  One                  goal of the research is the development of an asymmetric                        synthesis in which a chiral carbon is generated at the coupling                 site by the use of optically active transition metal catalysts.                                                                                                 In order to attain these objectives, a mechanistic understanding                of how an organotin reagent transfers an organic group to an                    organopalladium(II) halide will be sought.  The transmetallation                reactions of various organotin reagents with alkylpalladium(II)                 halides bearing a trans-chelating phosphine ligand will be                      carried out such that the transmetallation product cannot undergo               reductive elimination.                                                                                                                                          The synthesis of geometrically pure (E or Z) vinyl triflates and                their coupling reactions with organostannanes, particuarly                      vinylstannanes, will be explored in an effort to synthesize                     compounds containing the conjugated dienes, an important                        structural feature in a variety of biologically active products,                including certain conjugated polyenes derived from arachadonic                  acid.  The coupling reactions of aryl triflates will be explored,               and the reactions of both aryl triflates and aryl halides with                  vinylstannane will be developed for the synthesis of a number of                indole alkaloids.  Other useful electrophiles for coupling, such                as vinyl epoxides and alpha-halocarbonyls will be sought in order               to expand the scope of this reaction.  The effective use of a                   number of untested tin reagents should provide new synthetic                    pathways to a variety of products including a number of                         pyrethoids.  The utilization of this coupling chemistry in the                  synthesis of strained ring compounds also will be developed.
{'FirstName': 'Jack', 'LastName': 'Norton', 'EmailAddress': 'jrn11@columbia.edu', 'StartDate': '07/15/1987', 'EndDate': None, 'RoleCode': 'Principal Investigator'}
{'Name': 'Colorado State University', 'CityName': 'Fort Collins', 'ZipCode': '805232002', 'PhoneNumber': '9704916355', 'StreetAddress': '601 S Howes St', 'CountryName': 'United States', 'StateName': 'Colorado', 'StateCode': 'CO'}
[{'Code': '1950', 'Text': 'METHODOLOGY'}, {'Code': '1966', 'Text': 'SYNTHETIC INORGANIC'}]
{'url': 'https://www.nsf.gov/awardsearch/download?DownloadFileName=1987&All=true', 'xml': '8703218.xml'}