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Stereochemistry, Bonding and Formation

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

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

Stereochemical Outcomes in Transformations

What is the absolute stereochemistry of the asymmetric carbon in compound O? When compound O is treated with lithium diisopropyl amide, followed by allyl bromide, compound P is produced as a single stereoisomer. What is the absolute stereochemistry of the newly produced asymmetric carbon in P? Provide concise explanations for th

Which chair term will be more stable and explain why?

Draw the possible chair forms of cis and trans 1-isopropyl-3-methylcyclohexane. Are the two forms identical, enantiomeric, or diastereomeric? In each case, indicate which chair term will be more stable and explain why. Is either of these molecules chiral?

Determining a structure

I have tried to work out the following problem. Attached to this is a file that show NMR, IR and Mass spec info. I have come up with what I think the compound is but it does not work because the formula has more than one o. I have circled the carbonyl peak as well as the sp3 C-H peak.

Structures and fragmentation patterns in mass spectra

Suggest structure fragmentation patterns that account for the following observed peaks in the mass spectra. A) 5-methyl-2-hexanone, m/e= 71, 58, 43 B) C6H5CH2OCH3, m/e= 122, 121, 91, 77 C) 1-bromopropane, m/e= 124,122, 43, 29, 15

Conformation structures

A) Draw the most stable chair conformation of cis-1-cyclopropyl-2-methlcyclohexane. B) Draw the most stable conformation of trans-1-isobutyl-4-methylcyclohexane in both the chair conformation and the wedge structure.

Deriving Unknown Chemical Compound

I'm having some problems identifying the unknown compound based upon the information given. I provided as much information as I could with a possible compound, but I don't think it is correct. Can you please help me? Thanks! An unknown compound containing C, H, and one kind of heteroatom only shows a molecular ion peak

Steam Distillation

Steam distillation may be used to separate a mixture of p-nitrophenol and o-nitrophenol. The ortho isomer distills at 93 degrees Celsius, the para isomer does not. Explain.