5. Guaiacol : mass = 3 *10 -3 mol * 124.14 g/mol = 0.372 g (since 1 mol = 10 3 m

Question

5. Guaiacol: mass = 3 *10-3 mol * 124.14 g/mol = 0.372 g (since 1 mol = 103 mmol)

Sodium hydroxde: equivalents = 0.84 / 0.672 = 1.25, mmol = 1.25 * 3 = 3.75, mass = 121.93 g/mol * 3.75*10-3 mol = 0.457 g

Water: volume = (3.75 mmol / 0.84 * 1000 mmol) * 135 mL = 0.603 mL

3-chloropropane-1,2-diol: equivalents = 1.01 / 0.672 ~ 1.5, mmol = 1.5*3 = 4.5, mass = 110.54 g/mol * 4.5*10-3 mol = 0.497 g

Ethanol: volume 1 = (3 mmol / 0.672 *1000 mmol) * 400 mL = 1.786 mL

volume 2 = (4.5 mmol / 1.01*1000 mmol) * 84 mL = 0.374 mL

The total volume = 1.786 + 0.374 = 2.16 mL

Explanation / Answer

325final2015 (1).pdf Adobe Acrobat Reader DC 5 (1).pdf x +) | 74.9% Part II:"Dry Lab": Planning a New Reaction This final exam was written while its author was suffering from a bad cold. Attached to the exam is an excerpt from a publication (Bredikhin, A. A. et al. Tetrahedron: Asymmetry 2006, 17, 3015.) in which the authors synthesized guaifenesin, the active component in the expectorant Mucinex0 The supporting information for the paper provided the following procedure for performing a standard coupling at the gram scale. Some amounts are redactedxx") OCH OH OH 1) NaOH, aq. EtOH 2) OH Ci guaiacol guaifenesin rac-guaifenesin: To a solution of guaiacol (xx g. 0.672 mol) in ethanol (400 ml), a solution of NaOH (xx g. 0.84 mol) in water (135 ml) was added and the resulting mixture stired and heated at reflux for 30 min A solution of racemic 3-chloropropane-1,2-dicl (x g. 1.01 mol) in ethanol (84 ml) was then added within 30 min and the mixture was further stirred and heated at refhux for 8 h After cooling, the volume of the resulting mixture was reduced to about one third followed by the addition of water (400 ml) and extraction with CH Cl (8x 200 ml). The combined organic layers were dried over anhydrous Na SO, and the solvent was removed. Crude (product) was purified by distillation (bp 110-120°C at 0.05 mmHg) and recrystallization from CCL Yield 81.2 g (61%)mp 79-80°C: lit. mp 78.5-79.5 °C Imagine that you wished to conduct this experiment in the CHEM325 laboratory, using the equipment and resources that have been available to you this semester. Answer the followin questions, which walk you through steps that a practicing chemist would consider when planning to run a reaction for the first time

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