Synthesis of thiomorpholines
A scalable, photocatalytic coupling of silicon amine protocol (SLAP) reagents and aldehydes provides substituted morpholines, oxazepanes, thiomorpholines, and thiazepanes under continuous flow conditions in the presence of an inexpensive organic photocatalyst (TPP) and a Lewis acid additive.
M. K. Jackl, L. Legnani, B. Morandi, J. W. Bode, Org. Lett., 2017, 19, 4696-4699.
Boron trifluoride etherate mediates an intramolecular hydroalkoxylation/hydrothioalkoxylation of nitrogen-tethered alkenes providing five-membered thiazolidine, six-membered 1,4-oxazines (morpholines) and tetrahydro-2H-1,4-thiazines (thiomorpholines), and seven-membered 1,4-oxazepanes in good yields.
M. J. Deka, K. Indukuri, S. Sultana, M. Borah, A. K. Saikia, J. Org. Chem., 2015, 80, 4349-4359.