Interpretation:
The diastereomers structures for 2,3-diphenyl-2 butene are to be written and (E)-(Z) nomenclature has to be assigned.
Concept introduction:
The molecules that are nonsuperimposable or not identical with their mirror images are known as chiral molecules.
A pair of two mirror images that are nonidentical is known as enantiomers, which are optically active.
The objects or molecules that are superimposable with their mirror images are achiral objects or molecules and these objects have a centre of symmetry or plane of symmetry.
The achiral compounds in which plane of symmetry is present internally and consists of chiral centres are known as meso compounds, but they are optically inactive.
Diastereomers are the stereoisomers that are not mirror images of each other and are not superimposable on each other.
They possess different physical as well as chemical properties, because of difference in orientations.
In
In alkenes, if the higher priority group on both the carbon is on the opposite side, configuration is termed as E-configuration.
Want to see the full answer?
Check out a sample textbook solutionChapter FRP Solutions
EBK ORGANIC CHEMISTRY
- The reaction of 3,4-dimethyl-3-hexanol (3,4-dimethylhexan-3-ol) with HBr generates compound A as the major product. Treatment of compound A with a strong base gives two isomers of compound B as the major product, along with one isomer of compound C and one isomer of compound D as minor products, all of which have one double-bond equivalent. Identify compounds A, B, C, and D and give their names. By what mechanism does the reaction of 3,4-dimethyl-3-hexanol with HBr occur? By what mechanism does the reaction of A with strong base to form B occur? Propose reaction conditions for an alternative, one-step method for converting 3,4-dimethyl-3-hexanol directly to compound B.arrow_forwardb) Optical isomers can often be formed during these reactions. For products A-H indicate how many different optical isomers you expect to form for each from these reactions (you do not have to indicate whether they are diastereomers/enantiomers). c) In the preparation of substance D by ozonolysis, the second step is necessary treatment of the reaction mixture with zinc in acetic acid. If we forgot this step, we would get substance V instead of substance D, which would probably explode when isolated. What is the structure of substance V? *24 X 1: ozone V e) What products do you expect to form if they react with alkene X: I - HBr in diethyl ether; II - Brl in methanol; III - PhSCI in diethyl ether; IV - Selectfluor in methanol. P M EtOH NA EtONa PhSNa EtOH E H+ O TsCl Pyridín F- T2, Pd/C G4 mCPBA H₂SO4 10 %, H₂O 1: BH3 H◄ 2: H₂O₂ ill X Br₂ cyclohexane HCI A > В B HBr warmth, benzoylperoxid 1: ozone 2: Zn, ACOH Mg THF с D D₂O K I + J NaOHarrow_forwardPoly and B-Ryan are asked by their supervisor to synthesize (1R,3R)-1-chloro-1,3- dimethylcyclopentane. To accomplish their syntheses, Poly chooses to start from a trisubstituted alkene while B-Ryan chooses to start from a disubstituted alkene isomer. Poly's synthesis provides a mixture of isomers while B-Ryan's provides two stereoisomers. Both synthetic approaches are shown below. Me Me, Me, .CI Me HCI A B-Ryan's Synthesis Me 'CI + 75% 25% Ме Me Me Me... Me B Me C HCI A Poly's Synthesis -Me Ме 'CI 'CI + + Me.. .CI + a trace mixture ; of constitutional D Ме chloroalkane isomers Using your mechanistic knowledge of alkene reactions: (a) Explain the selectivity (regio and stereo) observed in B-Ryan's synthesis. (b) Propose a mechanism that accounts the formation of isomer C in Poly's synthesis. (c) Draw the major stereoisomer(s) formed in the "trace mixture of constitutional isomers" isolated in Poly's synthesis. 9.arrow_forward
- Conversion of an alkene to a halohydrin and internal displacement of a halide ion by an alkoxide ion are both stereoselective. Use this information to demonstrate that the configuration of the alkene is preserved in the epoxide. As an illustration, show that reaction of cis-2-butene by this two-step sequence gives cis-2,3- dimethyloxirane (cis-2-butene oxide).arrow_forwardThe reaction of 2,2-dimethyl-1-propanol [(CH3)3CCH2OH], also known by the common name neopentyl alcohol, with HBr is very slow and gives 2-bromo-2-methylbutane as the major product.Give a mechanistic explanation for these observations.arrow_forward(R)-2-butanol reacts with phosphorus tribromide to give A (C4H9Br). Treatment of A with sodium cyanide in DMF gives B (C5H9)N. B is optically active. Draw the structure of B. • Use the wedge/hash bond tools to indicate stereochemistry where it exists. Show stereochemistry in a meso compound. Sn [F ? ChemDoodleⓇarrow_forward
- The cis and trans isomers of 2,3-dimethyloxirane both react with −OH to give butane-2,3-diol. One stereoisomer gives a single achiral product, and one gives two chiral enantiomers. Which epoxide gives one product and which gives two?arrow_forward15) Ignoring stereochemistry, the 1:1 reaction of chlorine with 1,3-cyclohexadiene at 25°C in the dark and in the absence of peroxide forms which of these? C1 C1 C1 6 & 60 C1 I II III IV C1 C1arrow_forwardCompound W, C6H13Cl, undergoes base-promoted E2 elimination to give a single C6H₁2 alkene, Y. Compound X, C6H13Br, undergoes a similar reaction to form Y and an isomeric alkene Z. W is chiral; X is not. Catalytic hydrogenation of Y and Z produces 2-methylpentane. Propose structures for W and X. 0 • Do not use stereobonds in your answer. • In cases where there is more than one possible structure for each molecule, just give one for each. Draw one structure per sketcher. Add additional sketchers using the drop-down menu in the bottom right corner. Separate structures with + signs from the drop-down menu. -8) ChemDoodleⓇ Sn [Farrow_forward
- 3-Chloro-2-methylpropene reacts with sodium methoxide in methanol to form 3-methoxy-2-methylpropene. For each of the following changes in the reaction conditions, state whether the reaction rate would increase, decrease, or remain the same. Explain your reasoning. In some cases the identity of the major organic product would be expected to change; in such cases, give the expected major product. (a) the same quantities of reagents are dissolved in half the volume of methanol (b) 3-bromo-2-methylpropene is used in place of 3-chloro-2-methylpropene (c) sodium methanethiolate (CH3SNa) is used in place of of sodium methoxidearrow_forwardWhen it is treated with sodium ethoxide in deuterated ethanol (C2H5OD), cyclopentadiene exchanges all of its hydrogens for deuterium. Draw a structure for the intermediate in this reaction with all protons (no deuterons).arrow_forwardCompound X, C,4H12Br2, is optically inactive. On treatment with strong base, X gives hydrocarbon Y, C14H10: Compound Y absorbs 2 equivalents of hydrogen when reduced over a palladium catalyst to give z (C14H14) and reacts with ozone to give one product, benzoic acid (C,Hg02). Draw the structure of compound Z. • Use the wedge/hash bond tools to indicate stereochemistry where it exists. • Ignore alkene stereochemistry. • If more than one structure fits the description, draw them all. • Draw one structure per sketcher. Add additional sketchers using the drop-down menu in the bottom right corner. • Separate structures with + signs from the drop-down menu. ChemDoodlearrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning