THEY'RE TALKING New
Text
here's the latest on this high-yield reducing agent for carbonyl groups of aldehydes, ketones and acid haiides Briefly . • . M H I potassium borohydride ( K B H 4 ) is a white crystalline solid with a purity of 9 9 % and density of 1.175 g/cc. I t is completely stable and can be handled and stored safely in air without loss of purity. M H I KBH4 decomposes without melting in vacuum at 500°C with evolution of H 2 . O n hydrolysis, 1.66 liters of hydrogen are obtained from Ig of K B H 4. Specific Reductions . . . of carbonyl groups of aldehydes, ketones a n d acid haiides are fast and easy with M H I potassium borohydride. Without side reactions, without affecting other reducible groups present, without attacking oleflnic bonds, this versatile agent goes straight t o the h e a r t of t h e specific reduction, like this: —C—H + KBH
02N— O 11
CH3C
4
C2H5 + KBH
^
->o2isrOH I CH3C — I H
•o-
-CH20H
C2H5
Solubility. . . is 19.3 grams/100 grams water. Other solvents are water-methanol mixtures, in which solubility ranges from 13.0 grams/l00 grams solvent for a ratio of 4 t o 1 water-methanol solution clown t o 0.7 g r a m s / 100 grams solvent for methanol alone. I t also dissolves in other water-alcohol mixtures a n d liquid ammonia. In general, solubility sharply decreases with higher alcohols. KBH4 is generally insoluble in esters, ethers and hydrocarbons. I t has a negative heat of solution in water of 6.3 Kcal/mol. Equipment . . . Use conventional equipment, standard techniques. M H I potassium borohydride is easy and safe to handle. Your Applications . . . can be numerous and profitable. M H I sales engineers will gladly provide complete information concerning K B H 4 a n d its application t o your requirements. They will be h a p p y t o tell you, also, about how M H I Custom Reduction Service can carry o u t K B H 4 or any other hydride reductions for you on an economical basis. Why n o t call or write for details and technical literature. T h e r e is no obligation.
I C H E M 1 P A L H Y P R I D E QI V I ^ ' I O N.
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OCT.
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