Question

Experiment 8 - Addition to Alkenes What is Markovnikov's Rule? Chem 2321 In this experiment you will synthesize a brom ohydrin according to the reaction shown below. Using infrared (IR) spectroscopy and a simple chemical test, you will determine which product (Markovnikov or anti-Markovnikov) is formed. N-bromosuccinimide Br (NBS) но or н.о, THF ""сн, он "Br CH3 CH3 1-methylcyclohexene Markovnikov product anti-Markovnikov product Halogenation of alkenes is an important reaction in organic chemistry. When carried out in an aqueous solution, the major product is a halohydrin. In this experiment, you will synthesize a bromohydrin using 1-methylcyclohexene and N-bromosuccinimide (NBS) in a solution of water and tetrahydrofuran (THF). NBS is a chemical reagent that serves as a convenient source of cationic bromine. The mechanism of bromohydrin formation occurs in two steps: 1) formation of a bromonium ion intermediate and 2) nucleophilic addition of water to this intermediate. 1-methylcyclohexene is an unsymmetrical alkene, the addition of water can occur at more than one site Because to give regioisomeric products. We invoke Markovnikov's rule to predict the major regioisomer. The rule states that nucleophilic addition occurs at the more substituted carbon atom. We refer to the product of this addition as the Markovnikov product. The other regioisomer is referred to as the anti- Markovnikov product. In this experiment, you will synthesize the bromohydrin of 1-methylcyclohexa ne and determine if the product is consistent with Markovnikov's rule. Infrared (IR) spectroscopy and a Jones Oxidation Test will be used identify the product. The Jones Oxidation Test is a simple chemical test that gives an "immediate" visual result that can distinguish between a secondary and tertiary alcohol. The test involves an oxidation reaction that converts alcohols to ketones or carboxylic acids, depending on the alcohol. The general reactions are shown below. Primary alcohols are oxidized almost immediately, secondary alcohols react quickly, within a few minutes at most, and tertiary alcohols are not oxidized at all он СгОз H2SO CrO3 Он Cros H2SQ R H20 R H2SO4 Он R "RH2O Но R Он R R R R

Answer 1

Date IT What is the relation ship between the halohydrin products that you obtained in Hits reaction 2 Amsa A MBO, THÉ mentz 9-Methyl Markomi kov Anti Markomikov Cyclohexene product product (Halolydborim) I Haloky dorim) LNBS or br n Here betty halokydacims are structural isomers. because botts have some omoleculey formula and different bomding patterns and atomic or gimization Mechlewison :- o foronation of imaokomikov product:- Morkomikov xule states that the acidic hydrogen get attached to the carbon with more hydrogen substituents and the holide get attacked to the | carbon which is least_substituted. MBS t Kimc13 न ments Markomikov product

Date Anti markomikou product:- _ _Antimezkomikov gule indicates that lydrogen Latoms are attached to the carbom atom with the Heast hydrogen substituent the houg carb ason prote ther ki Bo PcH3 Antimarkenikov poodet. acti S e 0 (3) Explain the purpose of mixing 1 M Neck witte jod I Voux orawic laver after the reaction sdfs Sp Ans Additiom of Naol will Neutralize the acid presest" I in the organic layer which now goes into aqueles es Layer 03 How would you determine if you had residual Succinicide in your product Amses Succimiemide is insoluble in Fifo, hexane, cely land slightly soluble im water and Acom 479 Why are second zy alcohols able to unders en Oxidation reactions as opposed to tertiary Lakohols 3 Amse Tertiary alcohol (R304) are resistant to oxidatico 2 because the carbom atom that carries the-oh

groups does not have a hydrogen atom attached but is instead bonded to other cooboon atooms. > Mo reaction Ron secondary alcohol are oxidized to ketames and that's it. RAH TH20 ton secondry, ketime alcohol