Interpretation:
The reason corresponding to the formation of products in each of the given reactions is to be explained.
Concept Introduction:
▸ The molecules which are non-superimposable or not identical with their mirror images are known as chiral molecules.
▸ A pair of two mirror images which are non-identical is known as enantiomers which are optically active.
▸ The objects or molecules which are superimposable with their mirror images are achiral objects or molecules and these objects have a centre of symmetry or plane of symmetry.
▸ The achiral compounds in which plane of symmetry is present internally and consists of chiral centres are known as meso compounds but they are optically inactive.
▸ The stereoisomers which are non-superimposable on each other and not mirror images of each other are known as diastereomers.
▸ Chiral molecules are capable of rotating plane polarized light
▸ The molecules which are superimposable or identical with their mirror images are known as achiral molecules, and achiral molecules are not capable of rotating the plane-polarised light.
▸ Priority is given to all the four group attached to the chirality center.
▸ Priority is assigned on the basis of the
▸ If priority cannot be assigned according to
▸ After assigning priority to the four groups, rotate the molecule such that fourth priority group is away from the observer.
▸ Now, move from a to b to c; if the direction is clockwise, then the chiral center designated as
▸
▸ Z-isomers have the high priority group on the same side of the double bond whereas E-isomers have the high priority group on the opposite side of the double bond.
▸ In
▸ In alkenes, if the higher priority group on both the carbon is on the opposite side, configuration is termed as E-configuration.
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Organic Chemistry
- The reaction of (S)-2-bromopentane with potassium cyanide to yield 2-methylpentanenitrile (2-cyanopentane) occurs due to a nucleophilic substitution pathway. The reaction is 100% stereospecific. Please explain what this observation tells about the mechanism of the reaction.arrow_forwardThe reaction of butan-2-ol with concentrated aqueous HBr goes with partial racemization, giving more inversion thanretention of configuration. Propose a mechanism that accounts for racemization with excess inversion.(b) Under the same conditions, an optically active sample of trans-2-bromocyclopentanol reacts with concentrated aqueous HBr to give an optically inactive product, (racemic) trans-1,2-dibromocyclopentane. Proposea mechanism to show how this reaction goes with apparently complete retention of configuration, yet withracemization. (Hint: Draw out the mechanism of the reaction of cyclopentene with Br2 in water to give thestarting material, trans-2- bromocyclopentanol. Consider how parts of this mechanism might be involved in thereaction with HBr.)arrow_forwardCompounds X and Y are both C7H15Cl products formed in the radical chlorination of 2,4-dimethylpentane. Base-promoted E2 elimination of X and Y gives, in each case, a single C7H₁4 alkene. Both X and Y undergo an SN2 reaction with sodium iodide in acetone solution to give C7H15l products; in this reaction Y reacts faster than X. What is the structure of X? • Do not use stereobonds in your answer. • In cases where there is more than one possible structure for each molecule, just give one for each. . Draw one structure per sketcher. Add additional sketchers using the drop-down menu in the bottom right corner. Separate structures with + signs from the drop-down menu. наarrow_forward
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