The positive charge is shared equally by the three carbons indicated. Thus the two carbons ortho to the sp. e sp-hybridized carbon and the one para to it each bear one third of a positive charge (+0.33). None of the other carbons is charged. The resonance picture and the simple MO treatment agree with respect to the distribution of charge in cyclohexadienyl cation

SOLUTIONS TO TEXT PROBLEMS 13.1 The field strength of an NMR spectrometer magnet and the frequency of electromagnetic radia he Ire tion used to observe an NMR spectrum are directly proportional. Thus, the ratio 4.7 T/200 MHz is the same as 1.41/60 MHz. The magnetic field strength of a 60-MHz NMR spectrometer is

SOLUTIONS TO TEXT PROBLEMS 24.(b) A benzyl group(C., CH2) is ortho to the phenolic hydroxyl group in o-benzylphenol. OH CH2C.Hs (c)Naphthalene is numbered as shown. 3-Nitro-I-naphth has a hydroxyl group at C-1 and a nitro group

22.2 N,N-Dimethylcycloheptylamine may also be named as a dimethyl derivative of cycloheptanamine. -N(CH3)2 N,N-Dimethylcycloheptanamine 22.3 Three substituents are attached to the nitrogen atom; the amine is tertiary. In alphabetical order, the s substituents present on the aniline nucleus are ethyl, isopropyl, and methyl. Their positions are

20.1 () Carboxylic aci id anhydrides bear two acyl groups on oxygen, as in RCOCR. They are named as derivatives of carboxylic acids. Q CH:CH2CHCOH CH,CH,CHCOCCHCH_CH3 C6H C. C. 2-Phenylbutanoic acid 2-Phenylbutanoic anhydride (c) Butyl 2-phenylbutanoate is the butyl ester of 2-phenylbutanoic acid. CH,CH,CHCOCH,CH,CH2CH

SOLUTIONS TO TEXT PROBLEMS 21.1 Ethyl benz emuale cannor undergo the Claisen condensation, beca use it has no protons on its a- t has ho ts a-carbon on its a- atom and so cannot form an enolate Ethyl pentanoate and ethyl phenylacetate can undergo the Claisen condensation

Chlorotoluene Benzyl chloride Of this group only benzyl chloride is not an aryl halide; its halogen is not attached to the aromatic ring but to an sp-hybridized carbon. Benzyl chloride has the weakest carbon-halogen bond, its measured carbon-chlorine bond dissociation energy being only 293 kJ/mol (70 kcal/mol). Homolytic cleavage of this bond produces a resonance-stabilized benzyl radical

Look at the drawing from a perspective that permits you to see the carbon chain oriented ver tically with the aldehyde at the top and the Ch,oh at the bottom. Both groups should point away from you. When examined from this perspective, the hydrogen is to the left and the hydroxyl to the right with both pointing toward you

The order of decreasing sequence rule precedence is H,N->HSCH2->-Co2\>H- When the molecule is oriented so that the lowest ranked substituent () is held away from us, the order of decreasing precedence traces clockwise path CH,SH Clockwise;thereforeR The reason why L-cysteine has the configuration while all the other L-amino acids have the S configuration lies in the fact that the-CHSH substituent is the only side chain that

1、对中国社会主义运动史有一个初步的了解。 2、着重理解毛泽东社会主义观的发展演变情况及其对中国革命和建设的重要影响