Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 27.SE, Problem 47AP
Cembrene, C20H32, is a diterpenoid hydrocarbon isolated from pine resin. Cembrene has a UV absorption at 245 nm, but dihydrocembrene (C20H34), the product of hydrogenation with 1 equivalent of H2, has no UV absorption. On exhaustive hydrogenation, 4 equivalents of H2 react, and octahydrocembrene, C20H40, is produced. On ozonolysis of cembrene, followed by treatment of the ozonide with zinc, four carbonylcontaining products are obtained:
Propose a structure for cembrene that is consistent with its formation from geranylgeranyl diphosphate.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
α-Terpinene, C10H16, is a pleasant-smelling hydrocarbon that has been isolated from oil of marjoram. On hydrogenation over a palladium catalyst, α-terpinene reacts with 2 molar equivalents of H2 to yield a hydrocarbon, C10H20. On ozonolysis, followed by reduction with zinc and acetic acid, α-terpinene yields two products, glyoxal and 6-methyl-2,5- heptanedione.
(a) How many degrees of unsaturation does a-terpinene have?
(b) How many double bonds and how many rings does it have?
(c) Propose a structure for a-terpinene.
One compound that contributes to the “seashore smell” at beaches in Hawai‘i is dictyopterene D', a component of a brown edible seaweed called limu lipoa. Hydrogenation of dictyopterene D' with excess H2 in the presence of a Pd catalyst forms butylcycloheptane. Ozonolysis with O3 followed by (CH3)2S forms CH2(CHO)2, HCOCH2CH(CHO)2, and CH3CH2CHO. What are possible structures of dictyopterene D'?
Alloocimene is a hydrocarbon found in turpentine. It has the molecular formula C₁0H16 and a UV absorption maximum at 290
nm. On hydrogenation with a palladium catalyst, 2,6-dimethyloctane is obtained. Ozonolysis of alloocimene, followed by
treatment with zinc and acetic acid, produces the following four fragments:
||
CH3C-CH
i
O
||
||
CH3CCH3 HC-CH
Propose a structure for alloocimene.
O
||
CH3CH
Chapter 27 Solutions
Organic Chemistry
Ch. 27.1 - Carnauba wax, used in floor and furniture...Ch. 27.1 - Draw structures of glyceryl tripalmitate and...Ch. 27.2 - Prob. 3PCh. 27.2 - Write the saponication reaction of glyceryl...Ch. 27.4 - Prob. 5PCh. 27.5 - Prob. 6PCh. 27.5 - Prob. 7PCh. 27.6 - Draw the following molecules in chair...Ch. 27.6 - Lithocholic acid is an A–B cis steroid found in...Ch. 27.7 - Prob. 10P
Ch. 27.SE - Prob. 11VCCh. 27.SE - Propose a biosynthetic pathway for the...Ch. 27.SE - Identify the following fatty acid, and tell...Ch. 27.SE - Prob. 14MPCh. 27.SE - Prob. 15MPCh. 27.SE - Prob. 16MPCh. 27.SE - Prob. 17APCh. 27.SE - Fats can be either optically active or optically...Ch. 27.SE - Prob. 19APCh. 27.SE - Show the products you would expect to obtain from...Ch. 27.SE - Draw a Newman projection along the C2-C3 bond of...Ch. 27.SE - The plasmalogens are a group of lipids found in...Ch. 27.SE - Prob. 23APCh. 27.SE - Prob. 24APCh. 27.SE - Prob. 25APCh. 27.SE - Prob. 26APCh. 27.SE - Prob. 27APCh. 27.SE - Prob. 28APCh. 27.SE - Prob. 29APCh. 27.SE - Assume that acetyl CoA containing a 14C isotopic...Ch. 27.SE - Assume that acetyl CoA containing a 14C isotopic...Ch. 27.SE - Assume that acetyl CoA containing a 14C isotopic...Ch. 27.SE - Assume that acetyl CoA containing a 14C isotopic...Ch. 27.SE - Prob. 34APCh. 27.SE - Draw the most stable chair conformation of...Ch. 27.SE - Draw the most stable chair conformation of...Ch. 27.SE - Prob. 37APCh. 27.SE - Prob. 38APCh. 27.SE - Prob. 39APCh. 27.SE - What product would you obtain by reduction of...Ch. 27.SE - Prob. 41APCh. 27.SE - Eleostearic acid, C18H30O2, is a rare fatty acid...Ch. 27.SE - Prob. 43APCh. 27.SE - Prob. 44APCh. 27.SE - Propose a synthesis of diethylstilbestrol (Problem...Ch. 27.SE - Prob. 46APCh. 27.SE - Cembrene, C20H32, is a diterpenoid hydrocarbon...Ch. 27.SE - α-Fenchone is a pleasant-smelling terpenoid...Ch. 27.SE - Prob. 49APCh. 27.SE - Propose a mechanism for the biosynthesis of the...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.Similar questions
- Oximene and myrcene, two hydrocarbons isolated from alfalfa that have the molecular formula C10H16, both yield 2,6- dimethyloctane when treated with H2 and a Pd catalyst. Ozonolysis of oximene forms (CH3)2C = O, CH2 = O, CH2(CHO)2, and CH3COCHO. Ozonolysis of myrcene yields (CH3)2C = O, CH2 = O, (two equiv), and HCOCH2CH2COCHO. Identify the structures of oximene and myrcene.arrow_forwardIsoerythrogenic acid, C18H26O2, is an acetylic fatty acid that turns a vivid blue on exposure to UV light. On Catalytic hydrogenation over a palladium catalyst, five molar equivalents of hydrogen are absorbed, and stearic acid, CH3(CH2)16CO2H, is produced. Ozonolysis of isoerythrogenic acid yields the following products: formaldehyde, CH2O, malonic acid, HO2CCH2CO2H, adipic acid, HO2C(CH2)4CO2H, and the aldehyde carboxylic acid, OHC(CH2)6CO2H. Provide a structure for isoerythrogenic acid.arrow_forwardStructure of product C A hydrocarbon, A, with formula C11H16 undergoes hydrogenation with Pd to give product B, C11H22, and with Lindlar's catalyst to give product C, C11 H18. Ozonolysis leads to a mixture of products including cyclohexanone and 4-oxobutanoic acid. Treatment with sodium amide (NaNH2) followed by bromoethane gives compound D, C13H20. Draw possible structures for A, B, C, and D. H₂, Lindlar's Problem 13 of 14 Structure of A 1. NaNH2 Submit 2. CH3CH₂Br Structure of product Darrow_forward
- Compound A (C7H11Br) is treated with magnesium in ether to give B (C7H11MgBr), which reacts violently with D2O to give 1-methylcyclohexene with a deuterium atom on the methyl group (C). Reaction of B with acetone (CH3COCH3) followed by hydrolysis gives D (C10H18O). Heating D with concentrated H2 SO4 gives E (C10 H16), which decolorizes two equivalents of Br2 to give F (C10H16 Br4). E undergoes hydrogenation with excess H2 and a Pt catalyst to give isobutylcyclohexane. Determine the structures of compounds A through F, and show your reasoning throughout.arrow_forwardTreatment of a hydrocarbon A (molecular formula C9H18) with Br2 in the presence of light forms alkyl halides B and C, both having molecular formula C9H17Br. Reaction of either B or C with KOC(CH3)3 forms compound D (C9H16) as the major product. Ozonolysis of D forms cyclohexanone and acetone. Identify the structures of A–D.arrow_forwardCompound A (C7H11Br) is treated with magnesium in ether to give B (C7H11MgBr) which reacts violently with D2O to give 1-methylcyclohexene with a deuterium atom on the methyl group (C). Reaction of B with acetone (Ch3COCH3) followed by hydrolysis gives D (C10H18O). Heating D with concentrated H2SO4 gives E (C10H16), which reacts with 2 equivalents of Br2 to give F (C10H16Br4). E undergoes hydrogenation with excess H2 and Pt catalyst to give 2-methylpropylcyclohexane. Determine the structures of compounds A through F, and show your reasoning throughout.arrow_forward
- Compound A (C7H11Br) is treated with magnesium in ether to give B (C7H11MgBr), which reacts violently with D2O togive 1-methylcyclohexene with a deuterium atom on the methyl group (C). Reaction of B with acetone (CH3COCH3)followed by hydrolysis gives D (C10H18O). Heating D with concentrated H2SO4 gives E (C10H16), which decolorizestwo equivalents of Br2 to give F (C10H16Br4). E undergoes hydrogenation with excess H2 and a Pt catalyst to giveisobutylcyclohexane. Determine the structures of compounds A through F, and show your reasoning throughoutarrow_forwardHydrocarbon A has the formula C9H12 and absorbs 3 equivalents of H2 to yield B, C9H18, when hydrogenated over a Pd/C catalyst. On treatment of A with aqueous H2SO4 in the presence of mercury(II), two isomeric ketones, C and D, are produced . Oxidation of A with KMnO4 gives a mixture of acetic acid (CH3COOH) and the tricarboxylic acid E. Propose structures for compounds A-D, and write the reactions.arrow_forwardHydrocarbon A has the formula C9H12 and absorbs 3 equivalents of H2 to yield B, C9H18, when hydrogenated over a Pd/C catalyst. On treatment of A with aqueous H₂SO4 in the presence of mercury(II), two isomeric ketones, C and D, are produced. Oxidation of A with O3 gives a mixture of acetaldehyde (CH3COH) and the trialdehyde shown below. Propose structures for compounds A-D. CH,CHO OCHCH,CHCH CHOarrow_forward
- An achiral hydrocarbon A of molecular formula C7H12 reacts with two equivalents of H2 in the presence of Pd-C to form CH3CH2CH2CH2CH(CH3)2. One oxidative cleavage product formed by the treatment of A with O3 is CH3COOH. Reaction of A with H2 and Lindlar catalyst forms B, and reaction of A with Na, NH3 forms C. Identify compounds A, B, and C. Be sure to answer all parts.arrow_forwardThree isomeric pentanols with unbranched carbon chains exist. Which of these isomers, upon dehydration at 180C, yields only 1-pentene as a product?arrow_forwardWhen 2-pentene is treated with Cl2 in methanol, three products are formed. Account for the formation of each product (you need not explain their relative percentages).arrow_forward
arrow_back_ios
arrow_forward_ios
Recommended textbooks for you
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage LearningGeneral, Organic, and Biological ChemistryChemistryISBN:9781285853918Author:H. Stephen StokerPublisher:Cengage Learning
- Organic And Biological ChemistryChemistryISBN:9781305081079Author:STOKER, H. Stephen (howard Stephen)Publisher:Cengage Learning,
Organic Chemistry
Chemistry
ISBN:9781305580350
Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
Publisher:Cengage Learning
General, Organic, and Biological Chemistry
Chemistry
ISBN:9781285853918
Author:H. Stephen Stoker
Publisher:Cengage Learning
Organic And Biological Chemistry
Chemistry
ISBN:9781305081079
Author:STOKER, H. Stephen (howard Stephen)
Publisher:Cengage Learning,
IR Spectroscopy; Author: Professor Dave Explains;https://www.youtube.com/watch?v=_TmevMf-Zgs;License: Standard YouTube License, CC-BY