
Concept explainers
Name the following

a)
Interpretation:
The alkyne shown is to be named and the products formed when it reacts with 1) H2 in the presence of Lindlar catalyst and 2) H3O+ in the presence of HgSO4 is to be predicted.
Concept introduction:
The longest carbon chain which contains the carbon-carbon triple bond is chosen. The chain is numbered from the end that gives the lowest number to the carbon in triple bond. Compounds with more than one triple bond are called diynes, triynes and so forth. The substituents present, if any are written in the alphabetical order.
When reduced with Hydrogen in the presence of Lindlar catalyst the reduction of alkynes stops in the alkene stage. When treated with H3O+ in the presence of HgSO4, alkynes undergo hydration following Markovnikov regiochemistry to give an enols which will tautomerize to yield aldehydes (terminal alkynes) or ketones (internal alkynes).
To give:
The name of the alkyne shown and to predict the products formed when it reacts with 1) H2 in the presence of Lindlar catalyst and 2) H3O+ in the presence of HgSO4.
Answer to Problem 14VC
The name of the alkyne shown is 4,4-dimethyl-1-hexyne.
The product formed when it reacts with H2 in the presence of Lindlar catalyst is 4,4-dimethyl-1-hexene.
The product formed when it reacts with H3O+ in the presence of HgSO4 is 4,4-dimethyl-2-hexanone.
Explanation of Solution
The compound has a six carbon straight chain with two methyl groups on C4 with a triple bond between C1 & C2. Hence it’s name is 4,4-dimethyl-1-hexyne.
When reduced with hydrogen in the presence of Lindlar catalyst, the triple bond becomes a double bond as each of the two carbons in the triple bond gets attached to a hydrogen and an alkene, 4,4-dimethyl-1-hexene,is thus produced.
When treated with H3O+ in the presence of HgSO4, the addition of water takes place in the triple bond following Markovnikov regiochemistry. The OH group adds to more highly substituted carbon and H adds to the less highly substituted carbon in triple bond resulting in the formation of an enol which undergoes tautomerization to yield the ketone, 4,4-dimethyl-2-hexanone.
The name of the alkyne shown is 4,4-dimethyl-1-hexyne.
The product formed when it reacts with H2 in the presence of Lindlar catalyst is 4,4-dimethyl-1-hexene.
The product formed when it reacts with H3O+ in the presence of HgSO4 is 4,4-dimethyl-2-hexanone.
b)

Interpretation:
The alkyne shown is to be named and the products formed when it reacts with 1) H2 in the presence of Lindlar catalyst and 2) H3O+ in the presence of HgSO4 is to be predicted.
Concept introduction:
The longest carbon chain which contains the carbon-carbon triple bond is chosen. The chain is numbered from the end that gives the lowest number to the carbon in triple bond. Compounds with more than one triple bond are called diynes, triynes and so forth. The substituents present, if any are written in the alphabetical order.
When reduced with Hydrogen in the presence of Lindlar catalyst the reduction of alkynes stops in the alkene stage. When treated with H3O+ in the presence of HgSO4, alkynes undergo hydration following Markovnikov regiochemistry to give an enols which will tautomerize to yield aldehydes (terminal alkynes) or ketones (internal alkynes).
To give:
The name of the alkyne shown and to predict the products formed when it reacts with 1) H2 in the presence of Lindlar catalyst and 2) H3O+ in the presence of HgSO4.
Answer to Problem 14VC
The name of the alkyne shown is 2,7-dimethyl-4-octyne.
The product formed when it reacts with H2 in the presence of Lindlar catalyst is cis-2,7-dimethyl-4-octene.
The product formed when it reacts with H3O+ in the presence of HgSO4 is 2,7-dimethyl-4-octanone.
Explanation of Solution
The compound has an eight carbon straight chain with two methyl groups on C2 & C7 with a triple bond between C4 & C5. Hence it’s name is 2,7-dimethyl-4-octyne.
When reduced with hydrogen in the presence of Lindlar catalyst, the triple bond becomes a double bond as each of the two carbons in the triple bond gets attached to a hydrogen and an alkene, cis- 2,7-dimethyl-4-octene.is thus produced.
When treated with H3O+ in the presence of HgSO4, the addition of water takes place in the triple bond. As the alkene is symmetrical the Markovnikov regiochemistry cannot be applied. The OH group adds to one carbon and H adds to the other carbon in triple bond resulting in the formation of an enol which undergoes tautomerization to yield the ketone, 2,7-dimethyl-4-octanone.
The name of the alkyne shown is 2,7-dimethyl-4-octyne.
The product formed when it reacts with H2 in the presence of Lindlar catalyst is cis-2,7-dimethyl-4-octene.
The product formed when it reacts with H3O+ in the presence of HgSO4 is 2,7-dimethyl-4-octanone.
Want to see more full solutions like this?
Chapter 9 Solutions
Organic Chemistry
- 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 CI MgCl ? Will the first product that forms in this reaction create a new CC bond? Yes No MgBr ? Will the first product that forms in this reaction create a new CC bond? Yes No G टेarrow_forwardFor 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_forward
- Predict 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_forwardFor 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_forward
- Including activity coefficients, find [Hg22+] in saturated Hg2Br2 in 0.00100 M NH4 Ksp Hg2Br2 = 5.6×10-23.arrow_forwardgive 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_forward3-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_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning

