According to D u Pont, the onlv oreviously known compound of this type \v;is fluoroiminosulfur difluoride. In investigating reactions of the agent with caibunv! Lvuipouuds, Du Pont chemists find that fluorination of aldehydes and ketones gives good yields of difluorinated derivatives:
CHEMICALS N e w Agent for Fiuorinafion Du Pont's sulfur tetrafluoride replaces oxygen fluorine, opens door to new fluorinated products JULFUR
TETRAFLIOHIDL:—a
little-
known compound with unusual fluorinating ability—is now available in development (quantities from Du Pout's dyes and chemicals division, Wilmington, Del. The fluoride reacts with a variety of carboxylic acids and carbonyl compounds, including aldehydes, ketones, and quinones, to give new fluorine-containing products, according to Du Pont. And the fluoride simplifies the making of existing fluorine derivatives, the company adds. Sulfur tetrafluoride is not new to the chemical literature. But little of its chemistry was known until Du Pont chemists found a good way to make the compound and discovered that it could replace oxygen with fluorine in many compounds. Du Pont credits a large part of the new chemistry of sulfur tetrafluoride to three of its research chemists—Dr. Earl L. Muetterties, Dr. William C. Smith, and Dr. Charles W. Tullock. Dr. Muetterties and Dr. Smith worked on the preparation and
Briefs * * e • Liquid grain fumigant is now being made by Frontier Chemical, Wichita, Kan. The agent, called Clorofume, consists of chloroform, carbon disulfide, and ethylene dibromide. It has high insect toxicity, saves 20 to 309^ per bushel of protected grain, and is safe to handle, according to Frontier. C 2
• Nickel-containing catalyst to remove contaminants (especially nitrogen and sulfur) from catalytic reforming feedstocks is made by Universal Oil Products, Des Plaines, 111. The agent has low density, good heat stability, long life, and can be regenerated, UOP says. C3 • Laminated polyester film which can be molded into many shapes and forms 40
C&EN
AUG.
2 4,
1959
with
uses of sulfur tetrafluoride, and Dr. Tullock explored commercial methods of producing it. In the laboratory, Du Pont makes sulfur tetrafluoride by reacting sulfur dichloride with sodium fluoride suspended in acetonitrile at 7 0 - 8 0 ° C. (JACS, June 20, page 3 1 6 6 ) . O n e distillation gives over 90r'r pure sulfur tetrafluoride with thionyl fluoride as the main impurity, the company says. A gas at room temperature, the fluorinating agent must be handled carefully—it has an inhalation toxicity similar to that of phosgene and releases hydrogen fluoride on contact with moisture. Du Pont research on the uses of sulfur tetrafluoride turned up a new class of compounds—organoiminosulfur difluorides. These are made by reacting the fluorinating agent with compounds containing carbon-nitrogen multiple bonds: - N = C = 0 - f SF4 —*· - N = S F 2 -f- F2C = 0 — C = N -4- «F, —-* - C F 2 N = SF2
has been developed by Minnesota Mining & Mfg., Schenectady, Ν . Υ. Lamicoid LPF-1 consists of two plys of 10mil polyester film, laminated together by a bonding agent. The film has good flexibility and mechanical strength, good electrical properties, high heat re sistance, and good resistance to delamination, the company says. C4 • Liquid metallic siding both water proofs and insulates in one coat, accord ing to its developer, Pace Products, Kansas City, Mo. Available in differ ent colors, the product contains alu minum flakes and can b e brushed or sprayed on a surface. C5 k Low-foam iatex to coat pigmented paper has been developed by Koppers Co., Pittsburgh, Pa. Film strength of this styrene-butadiene latex is as much
C - O -f SF4
J^CF 2 -J- SOF 2
Some quinones, they find, react wliîi sulfur tetrafluoride like ketones, while others react to give fluorination and aromatization of the ring. Trifluorinated compounds can be made by reacting sulfur tetrafluoride with carboxylic acids, Du Pont says. Advantages: Reaction works well \v"th aliphatic, aromatic, and polycarboxylic acids; fluorination is selective—unsaturated acids give corresponding trifluoromethyl derivatives; i.e., acrylic acid gives trifluoropropene. Prospects for sulfur tetrafluoride? Addition of fluorine to steroids, tranquilizers, anticancer compounds, and the like has been known to give high potency drugs. Fluorine's ability to cause or modify biological activity in other chemicals could lead to use of the new agent to make improved insecticides and herbicides. And Du Pont foresees other uses: improved weather-resistant finishes, oils, films, plastics, and elastomers with high thermal stability and resistance to oxidation; surface active agents, water and oil repellents, and lubricants. C 1
as o0rA higher than that of conven tional latexes because of control of emulsifier content and of the polymeri zation reaction, according to Koppers. This increases pigment binding and pick resistance of the coated sheet, the company adds. C6 • Vinyl acrylic resin latex, by National Starch & Chemical, New York City, is designed to give lasting properties and high gloss to floor polishes. T h e resin has good leveling characteristics and makes polishes that are water resistant, the company adds. C7
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Further useful information on keyed Chemical items r«.>*y>*w· V^IIVIIIIVUI l l b l l l j | men | | « | | ~
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tioned is readily available . . .
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Use handy coupon on page 46 φ
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