Photocyclodimerization of 5-Methyl-2<i>H</i>-pyran-3(6<i>H</i>)-one
作者:Ljubov Groesch、Jürgen Kopf、Paul Margaretha
DOI:10.1002/hlca.200890239
日期:2008.12
The structures of the main products resulting from photocyclodimerization of the title compound 2 and of other 3-methyl-substituted ‘oxacyclohex-2-en-1-ones’ (=dihydropyranones) were determined by X-ray crystallography. In connection, the 13C-NMR chemical shifts of the cyclobutane C-atoms of these dimers allow a clear differentiation between head-to-head and head-to-tail regioisomers, all structurally