Nuclear magnetic resonance spectra chloroform

Carborane, Bk>C2Hi2, is quite soluble in aromatic solvents and is sparingly soluble in aliphatic solvents. The infrared spectrum has been previously reported.25 The proton nuclear magnetic resonance spectrum of a chloroform-d3 solution of carborane contains a broad CH resonance at 6.46 t. 

The nuclear magnetic resonance spectrum of valproic acid as shown in Figure 4 was obtained on a Varian Associates T-60 NMR Spectrometer as a 10% w/v solution in a solvent of deuterated chloroform. The spectral peak assignments (2) are presented in Table II. 

The infrared spectrum of y-crotonolactone shows two bands in the carbonyl r on at 5.60 and 5.71 fi in carbon tetrachloride (5%) [shifted to 5.61 and 5.71 fi in chloroform (5%)] and carbon-carbon stretching absorption at 6.23 fjt. The nuclear magnetic resonance spectrum shows olefinic peaks centered at 2.15r (pair of triplets) and 3.85r (pair of triplets), each due to one proton, and a two-proton triplet centered at 5.03t (in CCU). 

Fig. 1. —Nuclear Magnetic Resonance Spectrum of lA3,4-Tetra-0-acetyl-5-[(ben-zyloxycarbonyI)amino]-5-deoxy-a-D-xylopyranose (207). (Taken at 100 MHz in chloroform at 35° acetyl protons omitted the decoupled signals are indicated above tetra-methylsilane as internal standard.)...

C -(Dimethylpropylamine)carbaundecaborane(12) is a white crystalline solid, m.p. 191-192°. It is very soluble in acetone and tetrahydrofuran, slightly soluble in chloroform and methanol, and insoluble in benzene and water. The infrared spectrum (Nujol and hexachlorobutadiene mulls) contains major absorption bands at 2988(m), 2561(vs), 1481(m), 1472(m), 1414(m), 1130(m), 1035(m), and 934(m) cm. h The proton nuclear magnetic resonance spectrum (acetone-de solution) exhibits... 

Fig. 4.-—Nuclear Magnetic Resonance Spectrum of meto-Cyclohexanetetrol Tetraacetate, m.p. 118°, in Chloroform-d. [(A) At 60 mo. (B) at 100 me. (C) at 100 me., methylene protons irradiated.]...

Fig. 7.—Nuclear Magnetic Resonance Spectrum at 60 me. of Levorotatory ortho-Dimercaptocyclohexanetetrol Di-O-isopropylidene Acetal, m.p. 91°, in Chloroform-d.

Trimethoxyarsine (dj 1.4264 ng 1.4402) is a colorless liquid which is readily hydrolyzed by atmospheric moisture, forming a white precipitate of arsenic trioxide. The compound is soluble in carbon tetrachloride, benzene, chloroform, hydrocarbons, and ethers. The product is shown to be at least 99.5% pure (with respect to hydrogen-containing impurities) by proton nuclear magnetic resonance (n.m.r.), since a single sharp peak at —3.52 p.p.m. (relative to internal tetramethylsilane) is seen in the n.m.r. spectrum of the neat liquid. Similar properties are shown by triethoxyarsine (d 1.2132 ng 1.4360) and tri- i-butoxyarsine (dj 1.0723 nj 1.4476). 

The nuclear magnetic resonance (NMR) spectrum (Fig. 2) was obtained by preparing a saturated solution of meperidine hydrochloride, U.S.P. (Wyeth Lot No. F-665901) in deutero chloroform containing tetramethylsilane as internal reference. The only exchangeable proton is the hydrogen associated with HC1. The NMR proton spectral assignments are given in Table II. 

Nuclear Magnetic Resonance Spectroscopy ( H NMR and NMR) Proton and carbon nuclear magnetic resonance sp>ectra (iH NMR and NMR, respectively) were obtained in a polynuclear JEOL Eclipse Plus 400 sp>ectrometer (400 MHz), using tetramethylsilane as the reference and deuterated chloroform and carbon tetrachloride as the solvent for NMR and iH NMR, respectively. i3C NMR spectrum were accumulated during 24 hours. 

Another technique makes use of olefins to spin-tixq) short-lived Mu and make it observable in muonated fi ee radicals. In this way it was possible to prove that Mu is formed also in liquid chloroform or acetonitrile where it was never directly detected. This is shown in Figure 4 which presents Fourier spectra of the FID that was obtained with 0.2 M solutions of 2,3-dimethylbutadiene-l,3 (DMBD) in different solvents. At this concentration, DMBD can trap Mu on a time scale of ca. 40 ps in CHCI3 [17], The spin trap adduct is the 1,1,2-trimethylallyl radical which has the Mu atom substituted in the exo-methyl group. It shows up in the spectrum by two muon precession fi equencies, denoted R, which are the equivalent of the electron-nuclear double resonance (ENDOR) transitions in conventional magnetic resonance of fi ee radicals. 

---