Deconstructive Alkylation of Unstrained Cyclic Amines via Lewis Base–Boryl Radical-Enabled Spin-Center Shift

Deconstructive alkylation of unstrained cyclic amines is achieved through a boryl radical-enabled spin-center shift (SCS) strategy. Mechanistic studies, including control experiments and DFT calculations, support a pathway involving boryl radical addition to a carbonyl oxygen tether, followed by SCS-mediated C–N bond cleavage and ring opening, and subsequent radical trapping by alkenes. This transition-metal-free, non-redox protocol is compatible with a range of unstrained cyclic amines and alkenes, providing an efficient approach to skeletal modification of cyclic amines.