N-M-R...proved in action! Spectroscopy's
newest
r e s e a r c h t o o l is already playing an active role on leading laboratory teams throughout the nation. Serving varied research interests in universities, in industry and in government laboratories, it is daily making vital contributions to the study of molecular structures and chemical systems. A pioneer development of Varian Associates, the V-4300B High Resolution N-M-R Spectrometer, now available with the revolutionary new Super Stabilizer, is providing sensitivity and resolving power many times greater than that available in N-M-R's horse and buggy era just a few short years ago . . . offers a new approach to problems that resist solution by other means. Proven applications include quantitative and qualitative analyses of functional groups . . . hydrogen bonding studies . . . following molecular rearrangements... structural studies of natural products. Many promising biological and medical applications offer further evidence of N-M-R's significance in laboratory research. The operator is preparing to insert the sample into the sensing " p r o b e " of the Varian High Resolution N-M-R (Nuclear Magnetic Resonance} Spectrometer.
"THIS IS N-M-R AT WORK" NO.
SO OF A SERIES
S P E C T R U M A N D S T R U C T U R E O F THUJIC ACID The high resolution proton N-M-R spectrum has been used to confirm the structure of thujic acid. Since structure I has 5 protons attached to doubly bonded carbon atoms, while H has only three, an integration of the area of the resonance arising from these protons should solve the problem. This has been done and the area of the appropriate region which lies between A and Β was found to be 355 units, while the area of peak C was 210 units. Since peak C represents the 3 , methyl ester protons, there are clearly 5 protons on the ring and structure I is the correct one. 1 Acta Chemica Scandinavica 10, 487 (1956)
IF YOU WOULD LIKE MORE INFORMATION about N-M-R, write to the Instrument Division.
THE MARK OF LIADERSHIP
V A R I A N P A L O
A L T O
associates 4,
C A L I F O R N I A
Microwave Tubes . Instruments For further information, circle number 17 A on Readers' Service Card, paje 73 A
V O L U M E 2 8, NO. 10, O C T O B E R
1956
17 A
