Tetrahydrofuran moieties are found in a vast array of biologically important compounds and these structural subunits are frequently used as building blocks in natural product synthesis (some examples are shown here). [1] As a result, development of new methodology for the preparation of tetra-hydrofurans is an important objective in synthetic organic chemistry. [2] For example, cycloaddition of carbonyl ylide with C=C bond provides an easy entry for the formation of highly functionalized tetrahydrofurans. [3] We report here a new one-pot cascade reaction [4] for the construction of fully substituted tetrahydrofurans from aryldiazoacetates and allyl alcohols. This method provides an effective way to prepare fully anti-substituted tetrahydrofurans in a simple
Ylide chemistry has attracted a great deal of attention in recent years. [5] We discovered a novel oxonium ylide trapping transformation, [6] in which an alcoholic oxonium ylide can be trapped by electrophiles such as aldehydes, [7] ketones, [8] and imines. [9] This chemistry provided efficient methods for the rapid construction of polyfunctional molecules from simple starting materials. To extend this ylidetrapping chemistry, we designed an intramolecular trapping process hoping to use a Michael type C=C bond to trap an alcoholic oxonium ylide intermediate 4 (Scheme 1, path A). As a result, fully substituted tetrahydrofurans 3 could be constructed in one operation.
However, it was found that the inherent reaction kinetics didn't favor the desired reaction pathway in this case. The