Concept explainers
Interpretation: The type of cycloaddition occurs in the given reaction [1] is to be predicted. The similar product in the reaction [2] is to be drawn and whether these reactions occur in thermal or photochemical conditions is to be predicted.
Concept introduction: Cycloaddition reactions are pericyclic reactions that take place in two compounds containing pi bonds to form a cyclic compound. These reactions are concerted and stereospecific in nature. According to Woodward-Hoffmann rules, the polyene containing even number of bonds in thermal conditions undergoes reaction in antrafacial fashion and polyene containing odd number of bonds undergo reaction in suprafacial fashion. The total number of bonds present in the
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- 3. Explain in terms of bonding why ethene mostly undergoes electrophilic addition reactions. Draw the mechanism for the reaction of but-1-ene and hydrogen bromide. Show, via the mechanisms that are two different possible isomers – explain which one is formed preferentially and why this occurs.arrow_forward(Z)-3-methyl- pent-2 - ene is reacted with Br2 in CH3OH, as shown in the reaction scheme below.Complete the structure for one stereoisomer for the minor regioisomer formed in this reaction, including stereochemistry where appropriate. Draw both the wedged and dashed bonds at each stereogenic carbon atom.arrow_forwardA catalytic reduction of an alkene is shown below, what are all the possible products produced from this reaction. What is the relationship between the products? Is this a stereoselective, stereospecific reaction or neither? Explain. H2, Pd/Carrow_forward
- 2. Which one of these alkenes would be likely to experience a carbocation rearrangement when treated with aqueous acid (hydration)? A) B) C) D) None of these would undergo a rearrangement.arrow_forwardGenerally, addition of halogen acids to alkene follows Markovnikov rule. In which condition the anti-Markovnikov rule is followed? Describe the mechanism with an example.arrow_forwardRefer to the reaction energy diagram to answer parts (a) through (e). (a) The rate-limiting step is: ______. (b) The transition state for the fastest step is: _____. (c) In the third step which intermediate structurally resembles the transition state according to the Hammond postulate? _____. (d) Which step no. is endergonic? _____. (e) The number of intermediates in the overall reaction is: _____.arrow_forward
- Alkenes can be converted to alcohols by hydroboration-oxidation. (a) Draw the structure of the alcohol or alcohols formed in the reaction sequence. Clearly indicate stereochemistry by drawing a wedged bond, a dashed bond and two O Hint in-plane bonds per each chiral carbon. Draw hydrogen atoms that are connected to wedge-and-dash bonds.(b) Characterize the product or products of the reactions. The first step of the reaction, hydroboration, involves addition of BH, to the double bond, with -BH, attached to one carbon and hydrogen Be sure to draw hydrogens on oxygen, where applicable. attached to the other. Consider both Rings the regioselectivity and the Select Draw More Erase stereochemistry of this addition. H Diborane, B,H,, is a source of borane, BH,, and can be used 1. B2H6, interchangeably. Diglyme is a solvent. diglyme 2. H2О2, НО", The product or products of the reaction are characterized as being O S. O racemic. O achiral. O R,S (and/or S,R). O R. O S,S. O R.R. O diastereomers.arrow_forward(b) Addition of HBr to the alkene in the presence of peroxide form radical intermediates. Based on the following reaction, use the curved arrows to HBr B (preferred product) ROOR (i) show the initiation step of this reaction. (ii) draw the possible structures of the two radicals formed in the propagation step. (ii) explain the formation of the preferred product B.arrow_forwardDraw the alkene structure that produced the following compounds in a ozonolysis reaction as specified. 1. O3 2. (CH3)2S You do not have to consider stereochemistry. You do not have to explicitly draw H atoms. In cases where there is more than one answer, just draw one.arrow_forward
- A)What type of reaction is this? B) Draw ALL the products as required using any diagram typearrow_forwardA benzene ring alters the reactivity of a neighboring group in the so-called “benzylic” position, similarly to how a double bond alters the reactivity of groups in the “allylic” position. Benzylic cations, anions, and radicals are all more stable than simple alkyl intermediates. a) Use resonance structures to show the delocalization of the positive charge, negative charge, and unpaired electron of the benzyl cation, anion, and radical.arrow_forwardexplain and elaborate it please.arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage LearningOrganic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage Learning