During the investigation of the scope, we often observed a trace amount of reductive ring opening product 7. We speculated that 7 may be formed via a hydrogen atom transfer on the speculative biradical intermediate. As described in the quantum chemical computations (Scheme 3), a 1,3 biradical is always the most stable first intermediate generated from both bicyclic and linear cyclopropanes. We therefore speculated that a suitable HAT transfer reagent would allow to intercept the biradical intermediate in all cases, leading to a general homologation protocol. After optimization with several types of HAT reagents (See SI for detail), we were please to obtain reductive ring opening of product 7a starting from bicyclo [3,1,0] hexane derivative in 50% yield (Scheme 4B). The protocol only required the addition of 2 equivalents of diphenyl disulfide as a HAT reagent. Compared with previous studies on light-mediated ring-opening reduction of cyclopropanes, strongly reductive conditions were required, and the scope was limited to spiro cyclopropyl oxindoles 20a or aryl substituted cyclopropanes, 20b making these approaches not suitable for the development of a general homologation protocol. Several differently substituted-aryl cyclohexyl ketones 7b-h were obtained in yield ranging from 30 to 68%. The reaction is also possible for the formation of medium sized ring 7i in moderate yield. Starting from cyclopropanes 5a and 5c derived from the norbornene skeleton, products 7j and 7k were obtained in 54% and 45% yield respectively. For linear di-substituted carbonyl cyclopropanes 1a and 1b, only 1.2 equivalents of diphenyl disulfide are sufficient to furnish products 7l and 7m in good yields (69 and 89%). In contrast, 1.7 equivalents of diphenyl disulfide were required to reduce mono substituted or non-substituted carbonyl cyclopropanes, giving products 7n-q in 50 to 75% isolated yield. It is worth mentioning that a non-substituted cyclopropane can be used in this protocol, while no conversion was observed with the same substrate in the [3+2] annulation with alkynes. Starting from spirocyclic cyclopropane 1i, 60% of product 7r was obtained and the cyclobutane ring remained untouched, demonstrating the chemoselectivity of the reaction. Carbonyl cyclobutanes delivered products 7s and 7t. This strategy can therefore potentially be used as an alternative of the DeMayo reaction for the insertion of two carbon atoms.