Question

Show how you would accomplish the following synthetic conversion starting with ethanol as the only source of organic carbon atoms. You may use any necessary inorganic reagent and solvent. Show all reaction steps, reagents and conditions used.

Extra Credit: There will be no partial credit. Answers must be correct. (10 pts) Show how you would accomplish the following synthetic conversion starting with ethanol as the only source of organic carbon atoms. You may use any necessary inorganic reagent and solvent. Show all reaction steps, reagents and conditions used. OH OH ethanol 4-methylheptan-4-01

Answer 1

we know that ester on treatment with two moles op Goignard' seagent will produce a terialy alcohol. In this tertiary alcohol, among three alkyl groups two are same since they came from same Grignondpa gent. RgBri IR MB amg bo Lp ОН H20/47 RW We a will method, when contains two select this rah. a tertiary alcohol same go alkol groups.

Here, we have given a textary alcohol containing two propyl groups and are methyl group. so we can think this tertiasy alcohol could be formed from ester & propyl magnesium halides OH so we need toghs ethyl acetate Mg-By to pepele tertiary alcohol the given

But the condition given is these should be come are all ethand. from so first prepare them from ethanol xats on to Catts JL oxidation Synthesis oxidation o Crozit OH Estes formation OH OH + 0 Ethyl acetate

to prepare Now the problem is propyl group from ethyl group. we have a process creaction to lengthen chain, Here we need one CH2 group. The process of making next homologue C+CH) is called homologation, CH₂ - CH₂ - CH - CH2 - CH2 - The wsuitable reaction is Arndt Eistest synthesix. R ot R- CH₂ - {OH. us so let Ethand firxt convert Ethanolic acid caretic. to then acid. convert The it to resulted propanoic propansic

6 acid on reduction will give Propanol which on treatment with propyl bromide from HH PB8 gives which we can bromide get propyl Magnesium Arndt Eistest synthesia OH OH PBrz OH & CH] , Mg M9 --- I then

A.E. synthest soola 6 CHaNa H₂O LiAlHg O= PBr3 ~ Myn Br Me Br Mechanism Hosgrohot ores Hool)-044 H-on = LC O= 19 -Ha Н" -o-H -oh

oth Hotor OH ot O + C + H2O + oH 애 H2OTH -OH Ethanoic acid (or) Aretic acid. + C-4, los Leheime + soat

Eco + CH2-NEN Ü NEN C=CH-CH3 | H2O c. T CH CH₂ = SH-CH₂ H-Oye o= c ala-CH3 OH HO propanoic acidi

THAITH GAITH Н - Alt LOJAl-H +- (044) H + H AL-H Hood TH OH O AIH Propanol

H + Br Br Br -Br TOL Br By+ 0 = pByn J Mg, Etro Mgner M -By

4o-Mg-Br Cho T es - 5w0TH t Is-bw- Ig6w finally