192311-04-9Relevant academic research and scientific papers
Ring-Enlarging Cyclohexane Annulations
Ando, Sumie,Minor, Keith P.,Overman, Larry E.
, p. 6379 - 6387 (1997)
A Prins-pinacol rearrangement is the key step in a new method for synthesizing cis-bicyclo[n.4.0]alkanones. The alkenyl acetal rearrangement substrates 1 are assembled from cycloalkanone precursors in four steps (Table 1). Prins-pinacol rearrangement to form cis-bicyclo[n.4.0]alkanones 3 is best accomplished by exposure of 1 to 1 equiv of TMSOTf and a proton scavenger (2,6-di-tert-butyl-4-methylpyridine) at -78°C → rt.
Simplified analogues of qinghaosu (artemisinin)
Zhang, Qi,Wu, Yikang
, p. 10407 - 10414 (2008/02/12)
Three new simplified analogues of qinghaosu have been designed and synthesized through simple routes without recourse to the commonly employed photosensitized oxidation. The peroxy bonds in the target molecules were taken from UHP with the first peroxy-ca
Prins-pinacol spiroannulations
Minor, Keith P.,Overman, Larry E.
, p. 8927 - 8940 (2007/10/03)
Lewis acid-promoted cyclizations of methylenecyclohexane siloxy acetals 14, 15, and 21 afford spiro[4.5]decanones 22, 25, and 29 in good yield. In all cases, exclusive pinacol rearrangement of C-1 of the original three- carbon acetal side chain is observed suggesting that pinacol rearrangement of the intermediate 9-decalyl cation occurs more rapidly than conformational equilibration. This selectivity should allow Prins-pinacol spiroannulations to be employed in a predictable fashion to construct stereochemically complex spirocycles.
