This phosphonium salt is a classic Wittig reagent core raw material widely used in fine organic synthesis and pharmaceutical intermediate preparation. It generates sulfur-containing ylide under alkaline condition to realize olefination reaction for constructing methylthiomethyl substituted alkene skeleton, a key synthetic route for sulfur-containing API, pesticide intermediate and heterocyclic chemicals. In pharmaceutical industry, it is critical building block for synthesizing anti-virus, anti-bacterial and anti-tumor small-molecule drugs via carbonyl olefination with aldehydes & ketones. Besides bulk drug synthesis, it works as phase-transfer catalyst in multi-phase organic reaction to improve reaction conversion rate for lab custom synthesis and pilot-scale production. It is also used for preparing sulfur-containing polymer monomer and organic sulfur analytical standard sample, regularly stocked by fine chemical manufacturers for R&D institutes and pharmaceutical outsourcing factories worldwide.

GHS Classification：H315(Skin irritation), H319(Serious eye irritation), H335(Respiratory tract irritation)；Signal Word：Warning Risk Code:R36/37/38; Safety Code:S26, S36/37/39 Low acute oral toxicity, but hygroscopic solid dust irritates human skin, ocular and respiratory mucosa severely. Direct skin contact causes redness, itch and mild dermatitis; flush contaminated skin with plenty of running water over 15 min promptly after exposure. Powder splashing into eyes induces stabbing pain and conjunctiva inflammation, keep continuous eye washing for minimum 15 min and seek medical help if irritation persists. Inhalation of dust triggers throat dryness and cough; all weighing and feeding operations must proceed in ventilated fume hood with nitrile gloves, dust-proof goggles and disposable dust respirator. Store separately from foodstuff, strong acid, alkali and oxidants in moisture-proof low-temperature warehouse; waste solid and waste liquid shall be disposed as hazardous organic chemical waste complying with local environmental regulation, prohibited from random drainage into soil and water body.