The synthesis for DEET from 3-methylbenzoic acid has to be proposed. Concept Introduction: Reaction of acid chloride with ammonia or amines : The reaction of acid chlorides with ammonia and primary and secondary amines will yield amide. The nucleophilic addition of ammonia or amine to the carbonyl carbon occurs which is followed by a proton transfer forming an addition intermediate that will eliminate chloride and lose a proton to give the amide compound.

Question

(a 4 shows scanning electron microscope (SEM) images of extruded actions of packing bed for two capillary columns of different diameters, al 750 (bottom image) and b) 30-μm-i.d. Both columns are packed with the same stationary phase, spherical particles with 1-um diameter. A) When the columns were prepared, the figure shows that the column with the larger diameter has more packing irregularities. Explain this observation. B) Predict what affect this should have on band broadening and discuss your prediction using the van Deemter terms. C) Does this figure support your explanations in application question 33? Explain why or why not and make any changes in your answers in light of this figure. Figure 4 SEM images of sections of packed columns for a) 750 and b) 30-um-i.d. capillary columns.³

Answer 1

Question

Chapter 18, Problem 18.35P

Interpretation Introduction

Interpretation:

The synthesis for DEET from 3-methylbenzoic acid has to be proposed.

Concept Introduction:

Reaction of acid chloride with ammonia or amines:

The reaction of acid chlorides with ammonia and primary and secondary amines will yield amide.

The nucleophilic addition of ammonia or amine to the carbonyl carbon occurs which is followed by a proton transfer forming an addition intermediate that will eliminate chloride and lose a proton to give the amide compound.

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