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Lett."},{"key":"ref14\/cit14","unstructured":"Other metal triflates gave less satisfactory results. No reaction proceeded with Cu(OTf)2, In(OTf)3, and Zn(OTf)2. Some of other rare earth metal triflates promoted the reaction of imine2awith donor1a, but enantioselectivity was lower than La(OTf)3or comparable to La(OTf)3."},{"key":"ref15\/cit15","doi-asserted-by":"crossref","first-page":"1205","DOI":"10.1055\/s-2005-865315","author":"Weinreb A. M.","year":"2005","journal-title":"Synthesis"},{"key":"ref16\/cit16","unstructured":"Stereochemistry was determined by conversion to known compounds. See theSupporting Informationfor details."},{"key":"ref17\/cit17a","doi-asserted-by":"crossref","first-page":"2778","DOI":"10.1021\/ja057498v","volume":"128","author":"Trost B. M.","year":"2006","journal-title":"J. Am. Chem. 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