Quinuclidine and its derivatives as hydrogen-atom-transfer catalysts in photoinduced reactions

Hydrogen-atom-transfer (HAT) is an efficient way for direct CH functionalization of inert CH bonds, therefore it has attracted great interests in recent years. So far, various HAT catalysts have been developed. Among them, quinuclidine and its derivatives show different characters toward other HAT catalysts as they tend to abstract electron-rich and hydridic hydrogens in the presence of weak and neutral CH bonds. These features enable direct CH functionalization of compounds with various groups which are unable or difficult by other methods. This review summarizes recent advance of photoinduced reactions with quinuclidine and its derivatives as HAT catalysts and exhibits powerful synthetic potential by using quinuclidine and its derivatives as HAT catalysts.