✍ Scribed by Alexander J. Bridges; Hairong Zhou
No coin nor oath required. For personal study only.
Various 2‐fluorobenzonitriles were converted to the corresponding 3‐amino[1]benzothiophenecarboxylic acid esters, which in turn were annulated with formamidine or various equivalents to produce the desired tricyclic benzothienopyrimidines. Various methoxy and nitro/amino substituents were placed on the phenyl ring, requiring several different strategies to prepare the desired benzothiophenes. Several different pyrimidone annulations were also required. The use of an electron rich 2‐bromobenzonitrile in a four‐step one‐pot low temperature lithiation sequence to produce highly electron‐rich amino[1]benzothiophenecarboxylate esters is also described. The synthesis of 7‐amino‐8‐fluoro[1]benzothieno[3,2‐d]pyriinid‐4(3__H__)‐one was relatively straightforward, but synthesis of the corresponding 7‐amino‐8‐protio analogue proved to be very difficult, and required several approaches before a successful one was found.
📜 SIMILAR VOLUMES
## Abstract For Abstract see ChemInform Abstract in Full Text.
## Abstract The synthesis and the use of the five‐membered cyclic phosphorylating agents 1a–c are described. Their difunctional phosphorylating properties towards alkanols and hydroxylated amino acids and the cleavage reaction of the formed phosphoric acid triesters to diesters with oximate or plat