Organic Chemistry
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Identify the product(s) resulting from the reaction between the given alkene and (1) BH 3, THF followed by (2) H2O2 and NaOH.
Provide the alkene that produces the given alcohol upon hydroboration-oxidation. Take note of the relative (but not absolute) stereochemical outcome.
Provide a reagent for the following reaction forming an alcohol.
Draw the plausible mechanism for the formation of products in the reaction below.
What is the product of the following reaction under the specified conditions? Write "no reaction" if there is no reaction.
Identify the necessary reagents for the given reaction.
Determine the products for the reaction of the given molecule with (1) BH 3, THF and then with (2) NaOH and H2O2.
Predict the product(s) formed if the alkene shown below reacts with (1) BH 3, THF, and then with (2) H2O2, NaOH, H2O.
Draw the products formed when the following compound reacts with (1) BH 3, THF, followed by (2) H2O2 and NaOH.
Explain why the hydroboration reaction on 2,3-dimethylbuta-1,3-diene only gives a 1,2-addition product at any temperature.
Draw the structures of the products obtained from hydroboration-oxidation of cis-pent-2-ene.
Draw the structures of the stereoisomers produced from hydroboration-oxidation of (Z)-4,5-dimethyloct-4-ene.
Draw the products obtained in the reaction of cis-hex-3-ene and trans-hex-3-ene with the reagents given below. Show stereochemistry where applicable.
Propose a synthetic approach to produce the following compound from an alkene:
Draw the structures of the products formed when 1-ethylcyclopent-1-ene reacts with the reagents listed below. Include stereochemistry where appropriate.
Identify the missing product(s).
What reagents could be used to carry out the given reaction?
Show how to accomplish the synthetic conversion shown below.
Show how to synthesize the compound shown below from a cyclic alkene.
For each of the following reactions, determine the major products.(i) but-1-ene + BH3•THF →(ii) the product from part (i) + H2O2/HO− →
For each of the following reactions, determine the major products.(i) 2-methylhex-2-ene + BH3•THF →(ii) the product from part (i) + H2O2/HO− →
Show how the following synthetic conversion can be accomplished.pent-1-ene → pentan-1-ol
For the following reaction, determine the major products. Include stereochemistry in your answer.1−methylcyclopentene + BH3⋅THF then H2O2, OH-
For the following reaction, determine the major products. Include stereochemistry in your answer.trans-4,4-dimethylhex-2-ene + BH3â‹…THF then H2O2, OH-
For the following reaction, determine the major products. Include stereochemistry in your answer.
Two isomeric products are produced in the hydroboration-oxidation of (E)-3-methylpent-2-ene.(i) Give the structures of the products and determine the absolute configuration of each stereocenter in each of the structures you proposed.(ii) Identify the relationship between the two isomeric products.(iii) Determine the relationship between the products formed in the hydroboration-oxidation of (Z)-3-methylpent-2-ene and those formed in the hydroboration-oxidation of (E)-3-methylpent-2-ene.
For the following reaction, give the structures of the major products and propose the structures of any intermediates. Make sure you include stereochemistry in your answer.
Devise an approach for the synthesis of cyclopentylmethanol from methylenecyclopentane and any other required reagents.
Which of the following alkenes would give the desired alcohol via hydroboration–oxidation (1. BH3 2. NaOH, H2O2)? (Note: Pay attention to the relative stereochemical outcome.)
Draw the alkene that will undergo hydroboration-oxidation (1. BH3 2. NaOH, H2O2) to give the alcohol product below.
Like the pericylic reaction, hydroboration features a cyclic transition state. Draw the mechanism for the step shown below.
Determine the starting materials that are needed to synthesize the following alcohol.
What products are generated when the given compound is treated with the following reagents?
(i) 1. BH3 2. NaOH, H2O2
(ii) 1. Hg(OAc)2, H2O 2. NaBH4
Predict the product(s) of the following hydroboration–oxidation reaction. [The given molecule, while perhaps more complex than any you have seen previously, is, in the presence of borane, simply an alkene. The other functional groups present may be ignored.]
Show the product(s) of the hydroboration–oxidation reaction below. [The given molecule, while perhaps more complex than any you have seen previously, is, in the presence of borane, simply an alkene. The other functional groups and abbreviations present may be ignored.]
Starting from 3-ethylhex-1-yne, the alcohol 3-ethylhexan-3-ol can be prepared. Two other alcohols can be formed from the same starting material. Draw the structures of the two other alcohols that can be produced.
The reaction of an alkene with BH3 is more regioselective than its reaction with 9-BBN. Is this true?
Identify the products of the hydroboration–oxidation reaction of the following compounds.
(i) cyclopentene
(ii) 1-isopropylcyclopent-1-ene
Label each chiral center as R or S.
Explain why 3-isopropylcyclopent-1-ene should not be used as the starting material for a hydroboration–oxidation reaction with the target molecule shown below.
Show how CH3CH(CH3)CH2CH2CH2OH can be synthesized starting with a hydrocarbon of six carbons.
Provide the product(s) of the reaction shown below.