title: Gold(I)-catalyzed ring expansions of unactivated alkynylcyclopropanes to (e)-2-alkylidenecyclobutanamines in the presence of sulfonamides.
abstract: The ring expansion of cyclopropane derivatives provides a powerful method to construct synthetically useful four-membered carbocycles. Herein, a new type of gold(I)-catalyzed ring expansion of an unactivated alkynylcyclopropane/sulfonamide trapping strategy to (E)-2-alkylidenecyclobutanamines was described. The reaction tolerates a range of aryl and alkyl substituents with moderate to good yields.
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China.
authors.forename: Siyu
authors.initials: S
authors.lastname: Ye
authors.forename: Zhi-Xiang
authors.initials: ZX
authors.lastname: Yu
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D002082:Butylamines / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D020650:Combinatorial Chemistry Techniques; D003500:Cyclization; D003503:Cyclobutanes / Q000138:chemical synthesis* / Q000737:chemistry; D003521:Cyclopropanes / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism; D013449:Sulfonamides / Q000737:chemistry*
chemical_list: D000480:Alkynes; D002082:Butylamines; D003503:Cyclobutanes; D003521:Cyclopropanes; D013449:Sulfonamides; D006046:Gold