A study of the ring-contraction of a model 3H-naphtho[2,1-b]pyran is described in order to elucidate and optimise the ring-contraction of naphthopyrans. Two efficient basemediated protocols to access multiple naphthofurans, naphthodifurans and a benzo-fused indole in generally good yields are reported. Furthermore, a protocol to selectively prepare (hetero)aryl substituted naphthofurans via a Suzuki-couplingring-contraction process is presented. An additional protocol that allows Suzuki cross-coupling reactions to be performed on bromo-substituted naphthopyrans without the ring-contraction side reaction is reported.

The addition of sulfenes to substituted enaminoketones, followed by a facile Cope elimination, provides efficient access to a diverse series of 1,2-oxathiine 2,2-dioxides.

Multi-target synthetic strategies to access novel photochromic 3H-naphtho[2,1b]pyrans decorated with pyridyl units are described. The new pyridyl substituted 3Hnaphtho[2,1-b]pyrans display good photochromic properties with the reversible generation of photomerocyanines which exhibit mainly orange/red hues. Photochromic parameters including photocolourability and persistence of colour vary tremendously on structural modification of the naphthopyran core.

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