With a scalable route to 10-9, we first attempted a telescoped Risch type pyridine synthesis by subjecting 10-7, 10-9 and an amine source, such as hydroxylamine or ammonium acetate, to the condensation conditions (Scheme 15B). However, this process only gave a complex mixture of products. We then turned to a stepwise strategy involving a Knoevenagel condensation between 10-7 and 10-9, and mediated by ethylenediammonium diacetate. After the formation of the presumed enedione intermediate, a spontaneous thermal oxa-6π-electrocyclization delivered 2H-pyran 15-1 as the only product in 47% yield from crude 10-7 (see Supporting Information Scheme SI5 for more details).