(a)
Interpretation:
Based on the understanding of charge stability, it is to be determined which of the following compounds is expected to have the most similar pKa value to that of formaldehyde.
Concept introduction:
Table 6-1 refers to various compounds and their Ka and pKa values. Based on the structural similarities in compounds listed in Table 6-1 and their
(b)
Interpretation:
The pKa value for formaldehyde is to be estimated based on the concept of charge stability and the reference to Table 6.1.
Concept introduction:
pKa value represents the strength of an acid. The lower the value, the stronger the acid. Structural similarity in conjugate bases of two compounds indicates that the pKa values for the two compounds must be in the similar range. The chemical behavior of a compound is governed by the functional group it possesses.
Want to see the full answer?
Check out a sample textbook solutionChapter 6 Solutions
Organic Chemistry: Principles and Mechanisms (Second Edition)
- 6-137. The mixed aldol reaction between propionaldehyde (propanal) and acetone gives an 85% yield of 4-hydroxy-2- hexanone when run in THF at -78 °C with lithium diisopropylamide (LDA, a powerful base). The reaction is carried out by first adding the ketone to the base, cooling the solution, and then adding the aldehyde. (a) Why does this mixed system give essentially a single product? (b) Why is there no self-condensation of the acetone? (c) Why does the system not rapidly go on to dehydrate? (d) Why is the ketone added to the base rather than vice versa? ليك debudes for ketones) has no α-hydrogen atoms. This isarrow_forward8-8 Identify the major product(s) of the following reactions. Include stereochemistry. (a) (b) (c) Br NaOEt NaOEt NaOEtarrow_forwardWhich of the following bases are strong enough to deprotonate CH,CH,CH,C=CH (pK, 25), so that equilibrium favors the products? CH3CH,Li CH3ONA NH3 O H,0 CH;NHNA ONACH,(CO)N(CH3),arrow_forward
- Br OH H₂O HO (14 pts) Provide a complete mechanism for the reaction in the box. Include all electron-pushing arrows, lone pairs, and formal charges. HO blo NO (S)arrow_forwardUse curved arrow formalism to draw the mechanism of the reaction shown below. Include intermediates and their relevant resonance forms. Be sure to account for all the products. Br CH3OH OCH3 + Joc 1w OCH 3arrow_forward4. Predict the major product of the following reactions. NBS (a) 0°C Na,Cr,07 H,SO, H,0 (b) он H,SO4 CH,OH (d) heat Brarrow_forward
- Complete the synthetic sequence below by providing the structures of the reaction (questions 7-8). 1 mole of HOCH,CH,OH/H > B 1. LIAIH, 1.03 H* 2. Zn/H 2. Н.О. What is the structure of B? HO. (A) (D) OHarrow_forwardN-Nitrosamines by themselves are not significant carcinogens. However, they are activated in the liver by a class of iron-containing enzymes (members of the cytochrome P-450 family). Activation involves the oxidation of a C-H bond next to the amine nitrogen to a C-OH group. OH ОН N=0 N=O Og 'N- H+ H N,+ cyt P-450 N-Nitroso- 2-Нydroxy-N- nitrosopiperidine An alkyl diazonium ion piperidine (a carcinogen) Show how this hydroxylation product can be transformed into an alkyl diazonium ion, an active alkylating agent and therefore a carcinogen, in the presence of an acid catalyst.arrow_forwardHO CH30 Na A + B O,N pK =7 (a) Provide structures for A and B (including nonbonding electron pairs and formal charges where necessary), where A is the conjugate acid and B is the conjugate base of the reaction. Answer: (b) Provide and arrow pushing mechanism to show how A and B are formed. Answer: (c) Will the reaction proceed from left to right (i.e. are A and B favoured at equilibrium)? Explain your answer. Answer: (d) Draw all important resonance contributors of the conjugate base B. Rank the contributors from most stable to least stable (if contributors are equally stable indicate this with an equals sign)arrow_forward
- 20. Identify the product for each step in the following reaction sequence. Write complete equations showing the structure of all reactants and products for each step. (a) Isopropyl benzene + NBS/heat ---------->A (b) A+ t-BuOK ---------> B (c) B + 1)BH3 followed by 2)H2O2/NaOH -----> C (d) C + PCC ------> Darrow_forwardH 5+++ CH3COH H H LOSO₂Ar -H A H Solvolysis of this bicyclic compound in acetic acid gives a mixture of products. The leaving group is the anion of a sulfonic acid, ArSO,H. A sulfonic acid is a strong acid, and its anion, ArSO3, is a weak base and a good leaving group. Draw curved arrows to show the movement of electrons in the following step of the reaction mechanism. Arrow-pushing Instructions AOC XT H H H H H OCCH3 A-Harrow_forwardBr DMSO /H,O N-Br он N-H Br KO-Bu KBr HOt-Bu d- Electrophilic addition a- Proton transfer g- SyI Nucleophilic substitution h- Sy2 Nucleophilic substitution b- Lewis acid/base e-EI Elimination e- Radical chain substitution r-E2 Elimination Identify the mechanism by which each of the reactions above proceeds from among the mechanisms listed. Use the letters a - I for your answers. 1d 2. 2.arrow_forward