Sugar–boronic acid interactions in the formation of novel chiral porphyrin dimers with various porphyrin–porphyrin angles

Monoboronic acid-appended porphyrin 1 forms sugar–1 complexes (1:2) which have various porphyrin–porphyrin angles, depending on the sugar absolute configuration; the system is very useful in the study of the photochemical properties of dimeric porphyrins and the role of a so-called ‘essential pair’.