Efficient synthesis of 2H & 13C labeled benzaldehydes via regio-selective formylation

Benzaldehydes are important building blocks in synthetic organic chemistry that have wide applications for the synthesis of natural products and pharmaceutical drugs. Herein we report a general synthetic methodology for the synthesis of highly functionalized H-2 and C-13 labeled benzaldehydes in transfer of isotopic purity >99% via regio-selective formylation. Regio-selective deprotonation of substituted benzene 1 with LDA/n-BuLi at -78 degrees C and treatment with DMF-d(7) or EtO-(CHO)-C-13 led to the synthesis of 2-deutero-1,3-disubstituted benzaldehydes 2/4 in moderate to good yields. The synthetic methodology described represents a simple yet versatile route to functionalized formyl-deuterated, tritiated C-13 and C-14 labeled benzaldehydes. Published by Elsevier Ltd.