“…15,16 The high ring-strain 17 resulting from their inter-bridgehead C1-C3 bond has proven instrumental in various transformations. 18,19,20 More interestingly, the insertion of one-, two-, or three-carbon atoms to this strained bond via formal [n+2] cycloaddition reaction emerged as a powerful approach to access substituted bicyclo[1.1.1]pentanes (BCPs), 21,22,23 bicyclo[2.1.1]hexanes (BCHs), 24,25,26,27 and bicyclo[3.1.1]heptanes (BCHeps). 28,29 While numerous elegant transformations have been reported for the synthesis of such bicyclo[n. 1.1]alkanes, the methods for accessing related heterobicyclo[n. 1.1]alkanes remain under-explored.…”