© 2019 The Chemical Society of Japan. All-trans polyprenols consisting of one hundred carbons (C100) have been synthesized for the first time via the sulfone coupling of C45 and C55 fragments. The resulting coupling product with four benzenesulfonyl groups were subjected to desulfonylation reaction using Pd(dppp)Cl2/LiBHEt3 followed by removal of the benzyl group at the tail under Benkeser reduction conditions to furnish the title compound.