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Phosmet

Phosmet structure

CAS No:
732-11-6
Formula:
C11H12NO4PS2
Chemical Name:
Phosmet
Synonyms:
Phosphorodithioic acid,S-[(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)methyl] O,O-dimethyl ester;Phosphorodithioic acid,O,O-dimethyl ester,S-ester with N-(mercaptomethyl)phthalimide;Phosphorodithioic acid,O,O-dimethyl S-phthalimidomethyl ester;R 1504;O,O-Dimethyl S-phthalimidomethyl phosphorodithioate;Imidan;Phthalophos;Prolate;Stauffer R 1504;N-(Mercaptomethyl)phthalimide S-(O,O-dimethyl phosphorodithioate);Decemthion;Phosmet;O,O-Dimethyl S-phthalimidomethyl phosphorodithioate;O,O-Dimethyl S-(phthalimidomethyl) dithiophosphate;PMP (pesticide);S-Phthalimidomethyl O,O-dimethyl phosphorodithioate;Ftalophos;Decemthion P-6;Safidon;PMP;Imidathion;Simidan;Orbisect;Porect;Decemthion EK 20;Decemtion;Ordatox;Fosmet;Starbar GX 118;GWN 1976;Imidan 70WP
Categories:
Agrochemicals > Insecticides

Description

Phosmet is an off-white crystalline solid with an offensive odour.It is very soluble in acetone, xylene, methanol, benzene, toluene, and methyl isobutyl ketone; in kerosene. Phosmet is combustible and susceptible in the presence of strong reducing agents and hydrides. It forms highly toxic and flammable phosphine gas. On partial oxidation by oxidising agents, phosmet releases toxic phosphorus oxides. On heating and/or burning, phosmet decomposes and produces toxic fumes including nitrogen oxide

Phosmet Basic Attributes

Molecular Weight：

317.32

Exact Mass：

317.32

EC Number：

211-987-4

Characteristics

PSA：

113

XLogP3：

2.83

Appearance：

Phosmet is an off-white crystalline solid with an offensive odor. Used as an insecticide and acaricide. (EPA, 1998)

Density：

1.03 g/cm³ @ Temp: 20 °C

Melting Point：

71.9 °C

Boiling Point：

Decomposes below boiling point (EPA, 1998)

Flash Point：

>100 °C

Refractive Index：

1.636

Water Solubility：

Solubility in water, g/100ml at 20Â°C: 0.003

Storage Conditions：

0-6°C

Vapor Pressure：

Vapour pressure at 20Â°C: negligible

Toxicity：

Oral-rat LD50: 92.5 mg/kg; Oral-Mouse LD50: 26 mg/kg

Flammability characteristics：

Decompose toxic phosphorus oxide, sulfur oxide, nitrogen oxide gas by heating

Explosive limit：

Containers may explode in the heat of fire.

Odor：

OFFENSIVE ODOR

Safety Information

Packing level：

III

Hazard category：

6.1(b)

Transport codes：

UN 2811

wgk germany：

hazard class code：

21/22-50/53

safety instructions：

22-36/37-60-61

RTECS Number：

TE2275000

Marks：

Xn;N,N,Xn

Storage features：

The warehouse is ventilated, low temperature and dry; stored and transported separately from food materials

Stability/Shelf Life：

Relatively stable in acidic conditions. Decomposes rapidly above 100 deg C.

Precautionary statement(s)：

Missing Phrase - N15.00950417-P260-P280-P304 + P340 + P310-P403 + P233

Hazard Statements：

H301-H312-H330-H410

Toxicity

Toxicity class：

most toxic

Phosmet Use and Manufacturing

Methods of Manufacturing

Preparation of phthalimide Phthalimide (referred to as imide) is prepared by the action of phthalic anhydride and ammonium bicarbonate. The mixing ratio is phthalic anhydride: ammonium bicarbonate=1: 1.5 (mol); the reaction temperature is 280～300℃; the operation period is 6h. Preparation of N-hydroxymethyl phthalimide N-hydroxymethyl phthalimide (abbreviated as hydroxyl compound) is prepared by the action of imide and formaldehyde. The raw material ratio is imide:toluene=1:1.1, reaction temperature 98～100℃, heating time 1.5h, reaction time 3h, operation period 6～7h. Preparation of chlorinated methyl benzimide The hydroxyl compound reacts with hydrochloric acid to obtain chloromethyl benzimide (referred to as chloride). The raw material ratio is hydroxylate: hydrochloric acid ≈1:6.6, heating time 40～50min, reaction temperature (60±2)℃. The temperature of adding benzene is 55～58℃, the content of hydrochloric acid is 35%, and the operation period is 6h. For the preparation of sodium salt of O, O-xylene thiophosphoric acid, please refer to the preparation method of Dimethoate. Synthesis of iminothioate O, O-dimethyl sodium phosphorothioate reacts with chloromethyl benzimide to produce imidophos. The ratio of raw materials is hydroxylate: sodium salt=1: 1.01, reaction temperature is 50℃, heating time is 30min, reaction time is 2h, pH of reaction medium is 5-7, and operation period is 4-6h.

Uses

Insecticide, acaricide.

Computed Properties

Molecular Weight:317.3
XLogP3:2.8
Hydrogen Bond Acceptor Count:6
Rotatable Bond Count:5
Exact Mass:316.99453721
Monoisotopic Mass:316.99453721
Topological Polar Surface Area:113
Heavy Atom Count:19
Complexity:399
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes

Material

Benzyl chloride

Ammonium bicarbonate

Formaldehyde