A SUPERIOR REAGENT FOR:
NEW CHEMICALS Safe Reagent-Grade Bromine A bromine-charcoal reagent, Brom/ Saf, has been prepared for users who wish to avoid the hazards of liquid bromine. The reagent is ACS-grade bromine carefully adsorbed on charcoal (bromine assay: 40% minimum, 50% maximum). Halogen release is by ex traction with organic solvents, gentle heating of charcoal, or passing of heated air or steam through column. Brom/ Saf is offered in 1-lb amber jars with Teflon liners. Fisher Scientific Co., 300 Fisher Bldg., Pittsburgh, Pa. 501
Grignard Reagents Grignard reagents, ethyl magnesium chloride, methyl magnesium chloride, and phenyl magnesium chloride, are now available in tetrahydrofuran in stead of the traditional ethyl ether. These new certified reagents are sup plied in pint or gallon bottles. Fisher Scientific Co., 300 Fisher Bldg., Pitts burgh, Pa. 15219. 502
Rare Earth Chelates
Amino Acids . . . derivatized when dissolved. Foi nstance, cysteine is completely A new potentiated form of the ex trimethylsilylated in about ten linutes at room temperature — while an HMDS-TMCS xture gives incomplete substitution after three days at 45°. ceptional silylating agent "BSA" Highly Hindered Phenols . . . (Ν,Ο'-Bis- TMS -acetamide)...a even 2,6-di-t-butylphenol is rapidly converted to the TMS ether with BSA. convenient and ready to use A RAPID REAGENT FOR CARBOHYDRATES formulation with superior With Reservations . . . reagent characteristics. Recently, some rather exuberant claims for BSA have appeared,
TRI-SIL /BSA W A R N I N G : A l l T M S reagents and many T M S derivatives react instantly with water as well as other active hydrogen c o m p o u n d s . T o minimize nuisance peaks and to improve your results, always use a g o o d drying tube on your carrier gas line and pretreat your column with the T M S reagent several times before shooting a sample.
assigning extreme powers of silylation and total virtue to this reagent. Unfortunately, a careful reading of the literature tails to substantiate some of the more optimistic claims for power, speed, and panacea. Additionally, our own application studies on BSA (so far) indicate a high degree of anomerization under all conditions. If that one little drawback doesn't bother your work, T R I ' S I L / B S A * or BSA alone will do a fast, clean, job. However, our regular TRI-SIL will derivatize sugars just as rapidly, and with fewer side effects.
THE REAGENT OF CHOICE FOR STEROIDS? We're
not
sticking
our
corporate
neck
out that far
yet.
Our
development section issues reports varying from passionate to p r o f a n e , b u t t h e i n c i d e n c e o f e x c e l l e n t r e s u l t s is h i g h
enough
f o r u s t o s u g g e s t t h a t y o u g i v e it a t r y . A n d w e ' d b e d e l i g h t e d to hear of y o u r r e s u l t s , g o o d or b a d . SOLVENTS-Scrupulously
purified and dried.
— Nitrogen. P A C K A G I N G — Glass ampules c vials for m a x i m u m p r o t e c t i o n . A V A I L A B L E
ATMOSPHERE
elastomer capped T M S : 2.50
meq/ml
(1.25 m e q / m l f o r a m i d e s ) . 1 ml. A m p u l e s
25 m l .
P k g . o f 10
Serum Vial
4 9 0 1 1 7 T R I - S I L / B S A * in p y r i d i n e
12.50
14.00
4 9 0 1 0 7 T R I - S I L / B S A * in D M F
12.50
14.00
388371 B S A , pure
12.50
9.00/25 g
W r i t e o u r D e p t . A f o r a c o m p l e t e list of s i t y l a t i n g reagents related
and
bibliography
of
more
than
100
references.
* Tradename o! Pierce Chemical Co.
PIERCE CHEMICAL COMPANY P.O. Box 117 Rockford, Illinois 81105 P H O N E 81S-96847J7
T W X 910431-3419
Circle No. 7E on Readers' Service Card
NOW AVAILABLE...
Four volatile chelates of 2,2,6,6-tetramethylheptanedione with erbium, lan thanum, neodymium, and samarium are newly available. The chelates are thermally stable, anhydrous compounds of the general formula M ( t h d ) 3 . Both sublimed and practical grades are offered. Pierce Chemica" Co., Box 117, Rockford, 111. 61105. 503 Perfluorinated Fluids A new class of highly stable, inert, perfluorinated fluids (PFO-X) are now available. These fluids are described as linear oligomers of perfluorinated ethers with boiling ranges from 80° to 350° C. Molecular weigiits range from a few hundred to several thousand. Physical properties attributed to the PFO-X fuids are wide liquid range, ex treme chemical inertness, excellent thermal stability, good temperatureviscosity relationships, excellent dielec tric properties, and good lubricating properties. Suggested applications in clude their use as stationary liquid phases for gas-liquid chromatography. Peninsular ChemReseareh Inc., Box 14318, Gainesville, Fla. 32601. 504
4 Heavy Duly Magnetic Stirrers in i! Now have unmatched convenience and economy with four heavy duty magnetic stirrers in one by Henry TROEMNER! Four separate stirrers, driven by individ ual motors, are controlled by individual rheostats and on-off switches. Each stirrer is capable of uniform mixing up to four liters at 1000 rpm's! With Model 601 you get more versatility, more time-saving operation, more con venience than ever before! The sturdy, lightweight case design includes air cooling, sound-proofing and mounting rods at each stirrer location. Model 601 is priced at $285.00 f.o.b. Phila., and delivered ready for plug-in and use. Order now or write for litera ture: Henry TROEMNER, Inc., 6815 Greenway Ave., Phila., Pa. 19142. Model 600 available with 4 Synchronous Magnetic Stirrers!
TROEMNER
Circle No. 84 on Readers' Service Card
VOL 39, NO. 3, MARCH 1967
·
159 A
