A high yield procedure for the preparation of arsonolipids (2,3-diacyloxypropylarsonic acids).
The crucial step in the preparation of the title arsonolipids starting from the dichloromethane-soluble dithioarsonite CH(2)(OH)CH(OH)CH(2)-As(SPh)(2) is to avoid an internal cyclization during the acylation which protects the primary -OH group from being acylated. This was to a large extent accomplished by using fatty acyl chloride in the presence of the weak base pyridine and controlling the temperature and rate of the acyl chloride addition, giving approximately 70% yields of arsonolipids. The presence of catalytic amounts of 4-dimethylaminopyridine boosted the yields to 82-85%. This yield is a great improvement over the yields (20-55%) previously achieved. The acylating systems (RCO)(2)O or RCOCl and BF(3).Et(2)O gave only moderate yields (25-60%) of arsonolipids.
Ioannou
Panayiotis V
PV
Department of Chemistry, University of Patras, Patras, Greece. ioannou@chemistry.upatras.gr
Tsivgoulis
Gerasimos M
GM
D000215:Acylation; D001152:Arsenicals / Q000138:chemical synthesis / Q000737:chemistry*; D001880:Boranes / Q000737:chemistry; D002384:Catalysis; D011725:Pyridines / Q000737:chemistry
D001152:Arsenicals; D001880:Boranes; D011725:Pyridines; C021274:boron trifluoride; C054806:arsonic acid; C023666:pyridine