The synthetic strategies for π-expanded indolizines and indoles flourished in recent years. Despite this advancement, the lateral expansion of their polycyclic frameworks remains a relatively underexplored avenue, with only a few reported methods of limited scalability. To map the largely unexplored chemical space of linear polycyclic indoloindolizines, our objective was to establish a straightforward and scalable synthetic approach for these promising molecular architectures. Drawing inspiration from Dalcanale's pioneering synthesis of naphtho[2,3-b]indolizine-6,11-dione, we devised a solution-based protocol for a reaction between methylquinones and pyridine derivatives (Table ). Among the tested reagents and polar aprotic solvents needed to stabilize the postulated highly polar intermediates, DMSO at elevated temperatures, along with two equivalents of elemental iodine, yielded the best results in a test reaction between pyridine and 2-methylnaphthoquinone. This protocol enables the use of solid substrates, including π-expanded variants, which significantly broadens the reaction scope compared to Dalcanale's protocol. Applying these conditions to other methylquinones and pyridines we obtained a series of π-expanded indolizinequinones IQ in fair to good yields (Table ). Interestingly, while isoquinoline reacted readily, forming systems benzannulated at positions 7 and 8 of indoloindolizine, quinoline -which would result in benzannulation at positions 6 and 7 -did not react at all. This lack of reactivity is likely due to the poor reactivity of the C-H positions adjacent to the nitrogen in quinoline, which prevents ring closure from forming indoloindolizine. Indolizine-containing quinones IQ were further functionalized with trialkylsilyl-acetylenes using a streamlined one-pot protocol. The process commenced with the butyllithium-mediated addition of acetylene derivatives to the carbonyl groups of the quinones. The adducts generated from this reaction exhibited relative instability during purification attempts. Consequently, to circumvent this instability, a reductive elimination step was performed in the same reaction vessel. This was accomplished by introducing SnCl 2 along with a 10% aqueous HCl solution to give desired π-expanded indoloindolizines I in fair to good yields. For I5 and I10 the additions of TIPS-acetylene did not give a desired bis-adduct, presumably because of the steric clash between the large TIPS group and the rest of the molecule. TMS-acetylene was used instead to give desired products in acceptable yields (Table ).