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Stereochemistry, Bonding and Formation

Treatment of one stereoisomer of 2-iodo-3-phenylbutane

PROBLEM: Treatment of one stereoisomer of (2 ?, 3R)-2-iodo-3-phenylbutane with base, yields (E)-2-phenylbutene. a) Determine which enantiomer of 2-iodo-3-phenylbutene gives the E product (2R, 3R or 2S, 3R), and explain clearly (using unambiguous diagrams) why that is the case. b) Assign that enantiomer as either R or

Fischer projections

9. a. Using Fischer projections, draw all the possible stereoisomers 2, 4-dihydroxybutane (CH3-CHOH-CHOH-CH3) b. Label the relationships of your answers in "A" as enantiomers, diastereomers, or Meso ( if any) c. Assign absolute configurations to the chiral carbons n one of your Fischer projections. d. Indicate which of the

Aromatic compounds - trisubstituted derivatives

(See attached file for full problem description) How many possible trisubstituted derivatives C6H3X2Y can be obtained from the meta disubstituted benzene C5H4X2? (Ignore directive effects of the substituents X and assume that all positions on the ring are accessible to the reagent Y+)

Structures of Alkyl Halide

Match the structures below with the best description of the type of alkyl halide... See attached. Provide structures of products for the following reactions. Include 3-dimensional stereochemistry and absolute configurations where appropriate. If more than one product is possible, circle that which is predominant.

Organic Chemistry - Chlorination of Propane

The chlorination of propane yields 4 different dichloropropanes of formula C3H6Cl2. Using the following information to identify dichloropropanes A,B,C,D. i. If each dichloropropane is further chlorinated to yield trichloropropanes. Compound A gave one trichloropropane, B gave two, C and D each gave three. ii. Dichloropropane D

Hydrocarbon Chemistry Problems

1. For the compound, 1,2-dibromoethane, the most stable conformation would be a. eclipsed (0 degrees) b. gauche (60 degrees) c. eclipsed (90 degrees) d. anti (120 degrees) 2. The compound, 1,3-dimethylcyclobutane, is a constitutional isomer of which of the following? a. 1,3-dimethylcyclohexane b. 2,4-dimethylcyclobu

Enantiomer of cis-1-chloro-3-methylcyclopentane

Draw the enantiomer of cis-1-chloro-3-methylcyclopentane which is R at C-1. 1) What is the configuration of this molecule at C-3 (R and S)? 2) When cis-1-chloro-3-methylcyclopentane and trans-1-chloro-3-methylcyclopentane are treated with sodium iodide in aqueous acetone, their rates of substitution are strikingly differ

Organic Products

"Draw the structure of the major organic product of each of the following four reactions (one in the first file, two in the second file). Indicate stereochemistry if appropriate." Please see the attached files.

2-methyl 1-pentene

Consider the bromination of the compound 2-methyl 1-pentene in the attached file. 1. write the basic structure of the product of the bromination of 2-methyl 1-pentene, without regard to stereochemistry. 2. Does the product have any chiral carbons? If so, identify them with an circle. 3. How many stereoisomers are for

Tetrapeptides of 2 alanine & 2 valine

How many different tetrapeptides containing 2 molecules of alanine and 2 molecules of valine could theoretically exist? What are they? Write in shorthand.

Drawing Compound Structures

Draw the structure for: a) 4-methyl-2-chloro pentanal b) trans-3-chloro-2-fluoro cyclopentanone c) 3,5-dipropyl benzaldehyde d) 1,3 cycloheptadione

Molecular formula, structures, and functional groups

On the attached pages are the combined IR, 1H NMR and 13C NMR for Problems 1 and 2. Systematically solve the structure for each one. Provide the structure in the space attached, also, fill in the information requested on the table attached. Thank you!

HBr addition to a diene

I am trying to come up with a structure for a conjugated diene that would give the same product when HBr is added in either a 1,2-addition or in a 1,4-addition.

Reaction

There are actuallly two isomeric 2,4-dinitrophenylhydrazones of 2-pentanone. Draw the structures of these isomers. 2-pentanone also forms a derivative on treatment with semicarbazide. Note that semicarbazine has two -NH2 groups that might react with the carbonyl of the ketone to form the semicarbazone. Explain why it reacts as

Forming C5H9Br

When 1-pentene reacts with N-bromosuccinimide, two products with the formula C5H9Br are obtained. What are these products and how are they formed?

Structures for Compounds that are Optically Active

Compound A is optically active and has the molecular formula C5H10O. On catalytic hydrogenation (addition of hydrogen) of A, Compound B is obtained. Compound B has the molecular formula C5H12O and is optically inactive. Give the structure for Compounds A and B.

Stereochemistry: Structural Isomers or Dichloropentane

Structural Isomers Fill in the table on page 2 as described below for each structural isomer of dichloropentane. 1) Write a condensed structural formula. 2) Write the IUPAC name. 3. Give the number of chiral carbons. Go back to the structural formula and put an asterisk (*) next to each chiral carbon. 4) Construct and us

E and Z Stereoisomers

The stereochemistry of the more highly substituted alkenes is difficult to define using the cis and trans designations. Therefore, a more systematic manner of indicating stereochemistry in these systems has been developed that uses an E and Z nomenclature. Draw the structures of the E and Z stereoisomers of 1,4-diphenyl-2-butene

Major Organic Products for Reactions

1. Draw the structure of the major organic product for each of the reactions shown below. Be sure to indicate stereochemistry, where appropriate. A B