765292-86-2Relevant academic research and scientific papers
Titanium reagents for the synthesis of 2-substituted benzo[b]thiophenes on the solid phase
Roberts, Christine F.,Hartley, Richard C.
, p. 6145 - 6148 (2007/10/03)
Titanium(IV) benzylidenes (Schrock carbenes) bearing a masked sulfur nucleophile in the ortho position were generated from thioacetals with use of low-valent titanocene complex Cp2Ti[P(OEt)3]2 and alkylidenated Merrifield resin-bound esters to give enol ethers. Treatment of the resin-bound enol ethers with a 5:5:90 mixture of TFA, TFAA, and dichloromethane led to cleavage from resin, removal of the tert- butyldimethylsilyl (TBDMS) protecting group, and concomitant cyclization to complete the traceless solid-phase synthesis (SPS) of benzothiophenes. Switching the nature of the linker from acid-stable to acid-sensitive ensured good purity.
