Base catalysed synthesis of thiochromans and azo-linked chromenes using allenylphosphonatesElectronic supplementary information (ESI) available: Characterization data, copies of 1H/13C NMR spectra and CIF data. CCDC 885125-885130. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c2ob26285a

An efficient base catalysed approach to the synthesis of thiochromans/chromenes from allenylphosphonates (and an allenoate) and substrates having SH/OH and CHO groups at appropriate positions has been developed. Several azo-linked chromenes that are bright red pigments are also synthesized. This methodology involves the domino reactions of Michael addition and subsequent cyclisation by intramolecular aldol reaction. Under base catalysed reactions, an efficient route to synthesise thiochromans and azo-linked chromenes, that are bright red pigments, from allenylphosphonates is reported.