Triethyl Phosphite 99.9%, Grade : Purity Of 97% Or Higher, Packaging Size : 25KG

Triethyl phosphite is used as a ligand in organometallic chemistry and as a reagent in organic synthesis. It is used as reference to phosphoric acid standard in 31P NMR spectroscopy. It acts as a reducing agent to prepare 2-phenylindazole from o-nitrobenzylidineaniline as well as reacts with electrophiles to get phosphonates. It forms a stable complex with copper(I) iodide. It finds application in a modified Staudinger reaction for the alkyl bromide to an amine through the azide. Further, it is also used in the preparation of 3-phenyl-2-substituted indoles by reacting with beta-nitro styrenes.Triethyl phosphite is an organophosphorus compound. It is used as a reducing agent; can react with electrophiles to form phosphonates or phosphates; forms a stable complex with copper(I) iodide.This reaction is currently used for the preparation of synthetically useful phosphonate reagents employed in modified retinal studies. Thus, diethyl 3-alkoxycarbonyl-2-propenylphosphonates are prepared in 72-91% yields by the reaction of methyl or ethyl 4-bromocrotonates with triethyl phosphite at 150-160°C. Similarly, diethyl 3-(ethoxycarbonyl)-2 methyl-2-propenylphosphonate is prepared in 81% yield from triethyl phosphite and ethyl 3-methyl-4-chlorocrotonate by heating at 180- 200°C.The diethyl (E)- and (Z)-3-ethoxycarbonyl-3 fluoro-2 -methyl-2-propenylphosphonates are respectively obtained from triethyl phosphite and (E)- or (Z)-4-bromo-2-fuoro-3-methyl-2-butenoates at 140°C.

Triethyl phosphite is colorless, moderately toxic liquid, combustible. Flammable when exposed to heat or flame. When heated to decomposition Triethyl phosphite emits toxic fumes of oxides of phosphorus [Lewis, 3rd ed., 1993, p. 1271].

Triethyl phosphite is a very good nucleophile. The carbon adjacent to the bromine is the most electrophilic position, and phosphorus is the only nucleophile. Triethyl phosphite displaces the bromine in an SN2-like process, and back attack by the bromide which is released generates a phosphonate product, in which the α-protons are strongly acidic.The acute toxicity after oral, dermal, and inhalation exposure is relatively low. The oral LD50s in rats ranged between 1840 mg/kg bw (females) and 2470 mg/kg bw (males). Symptoms of rapid breathing and tremors were observed prior to death. In mice LD50 values above 3700 mg/kg bw were recorded. The 6-hour inhalation LC50 with an aerosol of 1.6-3.5 μm MMAD in rats was between 11,100 mg/m3 (females) and 11,600 mg/m3 (males). Clinical signs included eye and upper respiratory irritation, salivation and rapid, shallow breathing. The dermal LD50 in rabbits was between 2800 mg/kg bw (males) and > 3000 mg/kg bw (females).