Development of new chemical transformations involves an interplay of mechanistic insights, serendipity, and unbiased screening. The de novo prediction of organic reactions is complicated by low-energy side processes that decrease reaction selectivity and result in low yields. Productive reaction path modification is evidenced in interrupted processes, which take place when a high-energy state such as a reactive intermediate or a strained conformation takes on an alternate path. While this appears logical, there is a lack of actionable steps that allow for the design of such transformations. Motivated by discovery of spatioenergetically-matched reaction paths, we recently initiated a program aimed at structural modification of well-established intermediates and transition state assemblies. Although the principle of vinylogy 5 is restricted to consideration of ground states, an SN2' pathway 6 is effectively a vinylogous SN2 reaction (Scheme 1a). We felt that this way of looking at chemical reactivity might be applicable to other settings. Here we apply the principle of iminology 7 to epoxide ring-closure 8 and describe a hitherto unknown fragmentation reaction. 9 Unlike the double bond in vinylogy, the utility of the imino-fragment (C=N) as a two-atom relay unit has not garnered attention in the synthetic community. Structurally speaking, oximes can be considered as the iminologues of alcohols and related ethers and esters (Scheme 1b). Driven by the ongoing interest in the energy-rich N-O bond of oximes, 11 we considered the iminologue of 1,2-diols (1). Doing so appeared attractive because of the known migration, ring-closing and fragmentation transformations of 1,2-diols (Scheme 1c). Insertion of an imino fragment into the C-O bond of one of the hydroxy groups would afford structures such as 1, and subsequently the iminologous pseudohalohydrin upon oxime activation (Scheme 1d). Iminologous diol 1 can be obtained from commercially available 1,3-diones by a simple 2-or 3-step sequence (see Supporting Information). Three initial substrates, 1a-1c, were synthesized, and 1a was first reacted with 2 equivalents of KOtBu and a variety of reagents to activate the N-O bond to access the desired iminologous pseudohydrin in situ. The crude mixture was then analyzed by 1 H and 13 C NMR spectroscopy (Table ). The reaction of 1a with TsCl yielded a nitrile-containing species as indicated by 13 C NMR spectroscopy, in addition to a multitude of side products, which were difficult to separate by chromatography (entry 4). Other activating agents gave rise to the iminologous pseudohalohydrin without further reaction in conjunction with traces of other species with the characteristic nitrile 13 C signals (entries 1-3, 5). Treatment of 1a with DIPEA and TsCl, followed by KOtBu provided a more manageable reaction mixture, which was subjected to column chromatography to provide ketonitrile 2a and epoxynitrile 3a in a 3:1 ratio with a 31% combined yield (entry 6). Iminologous diol 1b underwent a similar fragmentation process to afford a mixture of 2b and 3b in a 1:1 ratio with a 26% combined yield (entry 7). Ketonitriles 2a-b presumably arose from a semipinacol rearrangement pathway via a carbocation intermediate (vide infra). By switching to more electron-deficient 1c, the epoxynitrile 3c was synthesized as the sole product and isolated in 78% yield, suppressing the competing semipinacol rearrangement (entry 8). Increasing the equivalents of base and activating agent raised the yield to 88% (entry 9).