Concept explainers
(a)
Interpretation:
The product formed by the reaction of D-galactose with NaBH4 and H2O has to be drawn in Fischer projection and the product is optically active or inactive has to be stated.
Concept Introduction:
The reaction of NaBH4 and H2O with carbohydrates is a reduction reaction. The carbonyl group in the carbohydrate is reduced to alcoholic group and forms alditols.
(a)
Explanation of Solution
The D-galactose is an aldohexose molecule. The carbonyl group present in D-galactose is
The formed alditol is optically inactive as it is a meso compound and shows plane of symmetry.
(b)
Interpretation:
The product formed by the reaction of D-galactose with H2/Pt has to be drawn in Fischer projection and the product is optically active or inactive has to be stated.
Concept Introduction:
The reagent H2/Pt is a reducing agent which reduces the carbonyl group into alcoholic group. The carbonyl group in the carbohydrate is reduced to alcoholic group and forms alditols.
(b)
Explanation of Solution
When the D-galactose molecule is made to react with H2/Pt, the aldehyde group is reduced to alcoholic group forming the alditol.
The formed alditol is optically inactive as it is a meso compound and it shows plane of symmetry.
(c)
Interpretation:
The product formed by the reaction of D-galactose with warm HNO3 has to be drawn in Fischer projection and the product is optically active or inactive has to be stated.
Concept Introduction:
The reaction of warm HNO3 with carbohydrates is a oxidation reaction. The carbonyl groups and alcoholic groups in the carbohydrate is oxidised to acid groups.
(c)
Explanation of Solution
The nitric acid (HNO3) is an oxidising agent. It oxidises the alcoholic groups and carbonyl groups into acidic groups. In D-galactose, the aldehyde group and the alcoholic group (C6) are oxidised to acid groups forming D-galactaric acid.
The product formed is a meso compound and shows plane of symmetry. So, it is optically inactive.
(d)
Interpretation:
The product formed by the reaction of D-galactose with Br2/H2O/CaCO3 has to be drawn in Fischer projection and the product is optically active or inactive has to be stated.
Concept Introduction:
The reaction of Br2/H2O/CaCO3 with carbohydrates is a oxidation reaction. The carbonyl group in the carbohydrate is oxidised to acid group. It is a mild oxidising agent compared to HNO3.
(d)
Explanation of Solution
When the D-galactose reacts with Br2/H2O/CaCO3, the aldehyde group is oxidised to acid group forming the acidic product, D-galactonic acid.
The formed product is optically active.
(e)
Interpretation:
The product formed by the reaction of D-galactose with H5IO6 has to be drawn in Fischer projection and the product is optically active or inactive has to be stated.
Concept Introduction:
The reaction of H5IO6 oxidises the carbohydrate molecule by cleaving the carbon-carbon bonds. It forms many cleaved products of the carbohydrate.
(e)
Explanation of Solution
The D-galactose molecule consumes 5H5IO6 molecules to cleave the six carbon-carbon bonds. The aldehyde group (C1) and hydroxyl groups (C2-C5) are reduced to acid groups and the C6 alcohol group is converted to aldehyde group. It forms six products among which five are formic acid molecules and one is formaldehyde.
The products formed are achiral and are optically inactive.
(f)
Interpretation:
The product formed by the reaction of D-galactose with aniline (C6H5NH2) has to be drawn in Fischer projection and the product is optically active or inactive has to be stated.
(f)
Explanation of Solution
The D-galactose molecule reacts with aniline molecule and the aldehyde group of carbohydrate is reacted with the
The formed product is a chiral compound and optically active.
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Chapter 25 Solutions
OWLv2 with MindTap Reader, 1 term (6 months) Printed Access Card for Brown/Iverson/Anslyn/Foote's Organic Chemistry, 8th Edition
- For each reaction below, decide if the first stable organic product that forms in solution will create a new CC bond, and check the appropriate box. Next, for each reaction to which you answered "Yes" to in the table, draw this product in the drawing area below. Note for advanced students: for this problem, don't worry if you think this product will continue to react under the current conditions - just focus on the first stable product you expect to form in solution. དྲ。 ✗MgBr ? O CI Will the first product that forms in this reaction create a new C-C bond? Yes No • ? Will the first product that forms in this reaction create a new CC bond? Yes No × : ☐ Xarrow_forwardPredict the major products of this organic reaction: OH NaBH4 H ? CH3OH Note: be sure you use dash and wedge bonds when necessary, for example to distinguish between major products with different stereochemistry. Click and drag to start drawing a structure. ☐ : Sarrow_forwardPredict the major products of this organic reaction: 1. LIAIHA 2. H₂O ? Note: be sure you use dash and wedge bonds when necessary, for example to distinguish between major products with different stereochemistry. Click and drag to start drawing a structure. X : ☐arrow_forward
- For each reaction below, decide if the first stable organic product that forms in solution will create a new C - C bond, and check the appropriate box. Next, for each reaction to which you answered "Yes" to in the table, draw this product in the drawing area below. Note for advanced students: for this problem, don't worry if you think this product will continue to react under the current conditions - just focus on the first stable product you expect to form in solution. NH2 tu ? ? OH Will the first product that forms in this reaction create a new CC bond? Yes No Will the first product that forms in this reaction create a new CC bond? Yes No C $ ©arrow_forwardAs the lead product manager at OrganometALEKS Industries, you are trying to decide if the following reaction will make a molecule with a new C-C bond as its major product: 1. MgCl ? 2. H₂O* If this reaction will work, draw the major organic product or products you would expect in the drawing area below. If there's more than one major product, you can draw them in any arrangement you like. Be sure you use wedge and dash bonds if necessary, for example to distinguish between major products with different stereochemistry. If the major products of this reaction won't have a new CC bond, just check the box under the drawing area and leave it blank. Click and drag to start drawing a structure. This reaction will not make a product with a new CC bond. G marrow_forwardIncluding activity coefficients, find [Hg22+] in saturated Hg2Br2 in 0.00100 M NH4 Ksp Hg2Br2 = 5.6×10-23.arrow_forward
- give example for the following(by equation) a. Converting a water insoluble compound to a soluble one. b. Diazotization reaction form diazonium salt c. coupling reaction of a diazonium salt d. indacator properties of MO e. Diazotization ( diazonium salt of bromobenzene)arrow_forward2-Propanone and ethyllithium are mixed and subsequently acid hydrolyzed. Draw and name the structures of the products.arrow_forward(Methanesulfinyl)methane is reacted with NaH, and then with acetophenone. Draw and name the structures of the products.arrow_forward
- 3-Oxo-butanenitrile and (E)-2-butenal are mixed with sodium ethoxide in ethanol. Draw and name the structures of the products.arrow_forwardWhat is the reason of the following(use equations if possible) a.) In MO preperation through diazotization: Addition of sodium nitrite in acidfied solution in order to form diazonium salt b.) in MO experiment: addition of sodium hydroxide solution in the last step to isolate the product MO. What is the color of MO at low pH c.) In MO experiment: addition of sodium hydroxide solution in the last step to isolate the product MO. What is the color of MO at pH 4.5 d.) Avoiding not cooling down the reaction mixture when preparing the diazonium salt e.) Cbvcarrow_forwardA 0.552-g sample of an unknown acid was dissolved in water to a total volume of 20.0 mL. This sample was titrated with 0.1103 M KOH. The equivalence point occurred at 29.42 mL base added. The pH of the solution at 10.0 mL base added was 3.72. Determine the molar mass of the acid. Determine the Ka of the acid.arrow_forward
