Gold(I)-catalyzed ring expansions of unactivated alkynylcyclopropanes to (e)-2-alkylidenecyclobutanamines in the presence of sulfonamides.
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.
Ye
Siyu
S
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.
Yu
Zhi-Xiang
ZX
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*
D000480:Alkynes; D002082:Butylamines; D003503:Cyclobutanes; D003521:Cyclopropanes; D013449:Sulfonamides; D006046:Gold