Aziridine ring system

1.) Explain why the neutral aziridine ring system is isoelectronic with the cyclopropyl carbion. 2.) Discuss the following: a.) What role does bromide play in the conversion of the trans-substituted aziridine to the diazabicyclo[3.1.0]hex-3-ene derivative? b.) Why is this particular bromide salt used ...continues

Oximes prepared from aldehydes or ketones

Oximes prepared from aldehydes or ketones by reaction with hydroxylamine can be reduced to primary amines in high yields. One can use various reagents for the reduction step including Ni-H2 in methanol or LiAlH4 in ether. Using a reduction reaction, carry out the following transformations: a.) 3-Pentanone to 3-aminopentane ...continues

C-H out of plane vibrations of the vinyl group

The form of the C - H out of plane bending vibrations of the vinyl group are shown below: The first two modes give rise to excellent group frequencies, while the third fundamental does not lend itself to these correlations. a.) Explain the factors that lead to the third mode being such a poor group frequency. b.) Predict the ...continues

Acetylene has two C-H groups

1.) Acetylene has two C-H groups. It will have two C-H stretching frequencies, the in-phase and out-of-phase stretching modes. The in-phase (symmetric) stretch occurs at 3374/cm and the out-of-phase stretch at 3333/cm. Explain why the in-phase vibration is located at a higher frequency than the out-of-phase stretch in the case o ...continues

Carbonyl stretching frequency of aliphatic carboxylic acids

1.) Carbonyl stretching frequency of aliphatic carboxylic acids in dilute solution is located near 1770/cm. This frequency is much higher than the carbonyl frequency of these substances when measured neat (1720/cm). Also it is considerably higher than the corresponding aliphatic ester (1745/cm) value. Explain 2.) The antisymm ...continues

Conjugation of functional group in alkyl isocyanates

Conjugation of functional group in alkyl isocyanates has little impact on the antisymmetric -N=C-O stretching vibration located near 2770/cm Explain.

Hydroxylamine

The hydroxylamine can be oxidized by MnO2 to the amide oxohaemanthidine. In dilute solution the carbonyl absorption band of oxohaementhidine occurs at 1702 /cm. Explain this observation.

Identifying unknown substances

Compound A (C7H14O) burned with a yellow, nonsooty flame and did not decolorize a bromine-methylene chloride solution. It did give a positive 2,4-dinitrophenylhydrazine test, but a negative Tollens test. Treatment of the compound with lithium aluminum hydride followed by neutralization with acid, produced a Compound B, which gav ...continues

Identifying unknown carboxylic acid

An unknown organic arboxylic acid, melting point = 139-141 degrees C, burned with a yellow, sooty flame. The sodium fusion test showed that nitrogen was present. It did not react with p-toluenesulfonyl chloride, but did give a positive test when tested with 5% aqueous ferrous ammonium sulfate solution, acidified with 3 N H2SO4 a ...continues

Identifying unknown substances

A friend of yours who is a graduate student attempting to establish the structure of a chemical species from field clover, isolated an alcohol that was found to have an optical rotation of +49.5 degrees. Chemical analysis gave a molecular formula of C5H10O. It was also observed that this alcohol readily decolorized Br2-CH2Cl2 so ...continues