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Stereochemistry, Bonding and Formation

Liquid crystals

Are there differences between the cholesteryl benzoates and the cholesteryl esters having long carbon chains? why or why not?

Organic Chemistry Questions: stereochemistry and chirality centers

See attached file for full problem description. 1. Write the complete stepwise mechanism for this reaction. Be sure to show all intermediate structures and all electron flow using arrows. 2. Predict the products of the following reaction. Indicate regiochemistry and stereochemistry when relevant.

Lewis structures and polarity of molecules

Draw the Lewis dot structure for the following molecules. Use VSEPR theory to predict three-dimensional structure. Then predict whether the molecule is polar or non polar. Sulfur dichloride Silicon tetrabromide Oxygen difluoride Nitrite ion

Multiple questions on monosaccharides, carbons, and sugars

I need the following questions answered in the next 45 minutes Thanks Sucrose is hydrolyzed to what two monosaccharides? 1. glucose and fructose 2. glucose and galactose 3. galactose and fructose 4. glucose and maltose Question 2 All chiral D-sugars rotate plane-polarized light 1. clo

Organic Chemistry

1. The compound 2-methyl-1,4-pentadiene would be classified as what type of diene? a. conjugated b. isolated c. cumulated d. internal 2. Select the least stable diene listed below: a. 2,3-pentadiene b. trans-1,3-pentadiene c. cis-1,3-pentadiene d. 1,4-pentadiene 3. Whic

Ozonolysis of alpha-terpinene

Ignore Structure A in the attached .jpg for this problem. Use only structures C and B Alpha -Terpinene, C10H16, a terpene found in coriander oil, absorbs only two moles of hydrogen, forming p-menthane, C10H20. Ozonolysis of Alpha -terpinene yields structure C in the attached .jpg; permanganate cleavage yields structure B.

Splitting pattern predictions

Help required for predicting the splitting patterns expected for each proton (proton 1 and proton 2) in 2,3-dimethylbutane. What is the number of adjacent hydrogens and what are the splitting patterns?

13C NMR spectral data

I need help with matching the spectral data to the correct structures. Please see attachment.

Stereochemistry of Anthracene and Polycyclic Benzenoid

I need some help with these two questions on stereochemistry, bonding and formation. 1. There are four reasonable resonance structures for anthracene. Draw them. 2. A large number of polycyclic benzenoid aromatic hydrocarbons are known. One of these, benz/a/pyrene, is a powerful carcinogen found in tobacco smoke. From the

SN1 Mechanism

(See attached file for full problem description with reaction) --- Consider the reaction below: If the above reaction occurs via an SN1 reaction mechanism, then propose an explanation for why a racemic mixture is not formed in this reaction. ---

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

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+)

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

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

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.


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

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

Identifying Structures from Spectra

Please identify the structure giving the following spectra (NMW, IR, Mass Spec, etc.) (attached) and state how you arrived at your structure (give reasons such as peak identifcation and mass, etc.).

Products attached to C3, etc.

I attempted some of this but I am clueless as to some of the other stuff. Can you help? 2) Why are the products attached to C3 of 1,4 pentadiene more acidic than the methyl hydrogen atoms of propene? Maybe you can help me with this one. Are the C3 atoms more acidic because there is more s character involved with the ato