Crotyloxymethyltriphenylphosphonium Chloride

Abstract

[188476-03-1] C23H24ClOP (MW 382.8678) InChI = 1S/C23H24OP.ClH/c1-2-3-19-24-20-25(21-13-7-4-8-14-21,22-15-9-5-10-16-22)23-17-11-6-12-18-23;/h2-18H,19-20H2,1H3;1H/q+1;/p-1/b3-2+; InChIKey = NIXWHXJMJWCZIC-SQQVDAMQSA-M Alternative Names: crotyloxymethyltriphenylphosphonium chloride ((but-2-en-1-yloxy)methyl)triphenylphosphonium chloride crotyloxymethylene triphenylphosphonium chloride. Physical Data: white crystalline solid, melting point 145–147 °C.1 Solubility: insoluble in tetrahydrofuran, diethyl ether, ethyl acetate, and toluene. Soluble in dichloromethane and chloroform, also soluble in water. Form Supplied in: white amorphous solid. Analysis of Reagent Purity: the reagent is analyzed by NMR and Infra-Red spectroscopy, IR (cm−1): 1622, 1590, 1441, 1220, 1110, 9121; 1HNMR (90 MHz, CDCl3) δ 1.53 (d, 3H, 5.39 Hz, CCH3), 4.18 (d, 5.65, Hz, 2H, OCH2), 5.34(m. 2H), 5.62 (d, 4.12 Hz, 2H, P-CH2O), 7.66 (m, 15H).1 Preparative Methods: crotyloxymethyltriphenylphosphonium chloride is prepared from crotyl alcohol (but-2-en-1-ol). Chilled crotyl alcohol is treated with anhydrous HCl gas in presence of paraformaldehyde to provide crotyl chloromethyl ether (eq 1).1 This is a solvent-free reaction and requires continuous bubbling of HCl gas through the reaction mixture. The HCl gas is generally prepared by dripping concentrated sulfuric acid onto the lumps of oven-dried NaCl. The product chloro-ether is recovered by distillation. The process for the preparation of the crotyl chloromethyl ether is the same as the preparation of allylchloromethyl ether.2,3 (1) Crotylchloromethyl ether obtained in this way (eq 1) is allowed to react with triphenylphosphine in toluene at room temperature to afford the product (eq 2) in the form of a white amorphous solid. (2) The solid is recovered by vacuum filtration and dried on a rotary evaporator at 95 °C. The product obtained is stored under nitrogen at room temperature. The product is a stable, slightly hygroscopic solid, and can be stored for approximately two years, without any deterioration in the quality. The preparative process of the reagent corresponds to the preparation of allyloxymethyltriphenylphosphonium chloride salt.2–4 Handling, Storage, and Precautions: the reagent is moderately hygroscopic and forms a sticky substance on the skin. Gloves should be worn while handling this reagent. It is irritating to the eyes and nasal linings. The use of a mask or face shield/visor is suggested while weighing and transferring into the reaction vessel. Stability and toxicity data are not currently available in the literature; the corresponding information for allyl chloroformate should be consulted.