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10.1007/s11178-008-2001-z

“…A similar in structure dilithium intermediate was obtained by the reaction of the metal with spirooxirane 153 [12] (Scheme 77).…”

Cage-like amino alcohols. synthesis, reactions, and application

“…The regioselectivity of oxirane ring opening conforms to the Krasuskii rule which was formulated while studying aminolysis of alkyl-substituted oxiranes; according to this rule, the formation of more substituted alcohols is preferred. The regioselectivity is controlled by steric factor: nucleophilic attack by an amine at less substituted (and hence more sterically accessible) carbon atom in the oxirane ring is more favorable [1,[31][32][33][34][35][36][37]. This factor is responsible for higher reactivity of terminal epoxides in reactions with amines, as compared to internal epoxy derivatives.…”

The Radziszewski oxidation of cycloalkylidene‐α‐(thiazol‐ 2‐yl)acetonitriles: A new approach toward spirooxiranes

“…As they are versatile, highly reactive, and chemically flexible reagents, a considerable attention has been devoted to both the methods of epoxidation and reactions of oxiranes (for recent reviews on the methods of epoxidation and chemical transformations of oxiranes see, e.g., [1][2][3][4][5][6]). Spirooxiranes (or 1-oxaspiro [2.n]alkanes) are of special interest because their biological profile and specific reactions, in some cases, could be vastly different from those reported for other oxiranes [2,7].…”

“…The direct epoxidation of 1methylenecycloalkanes to spirooxiranes has been suc-cessfully accomplished with only a few epoxidizing agents such as dioxiranes [14] (for reviews on the dioxirane epoxidation see [15]), monoperphtalic acid [16], pnitroperbenzoic acid [17], m-chloroperbenzoic acid (MCPBA)-NaHCO 3 system [18], or OxoneV R (2KHSO 5 Â KHSO 4 Â K 2 SO 4 )-cyclohexanone-phosphate buffer [19]. Noteworthy that organic peroxy acids could be used for epoxidation of methylenecycloalkanones, but reaction is frequently accomplished with low ratio of exo/endo enantiomers [2] and often complicated by side reactions such as acid-promoted oxirane ring cleavage and rearrangements [2,6,7,20]. For instance, the epoxidation of methylenecyclopropanes with MCPBA is accompanied by rearrangement resulted in formation of cyclobutanones as sole products [21].…”