Trimethylmethane diradical(TMM diyl) has drwan attention from physical organic chemists for their peculiar properties and from synthetic chemists for their exceptionally high reactivity. Though, TMM diyl has not been widely used as a synthetic intermediates due to the limited syntheci methodologies to generate TMM diyls. To expand the applicability of TMM diyl in organic synthesis, we have been developing new synthetic methodologies for TMM diyl generation.
Recently, we have developed a mild and general way of generating TMM diyls through intramolecular [2+3] cycloaddition reaction of diazo compounds with allenes. Through this strategy, TMM diyls with wide variety of substitution pattern were prepared and subsequent [2+3] cycloaddition reaction with olefins produced polyquinanes such as linear triquinanes, angular triquinanes and tetraquinanes with high efficiency. This new synthetic methodology was successfully applied to total synthesis of polyquinane natural products. The scope the new synthetic methodology and facile total synthesis of these natural products through this methodology will be presented.