1). What would be the reason to observe a wide melting point range or a deviated melting point from the literature value for the final product of this reaction? Be specific. 

2). If you wanted to make pure (S)-(+)-guaifenesin, what reagent would you need to use in place of one that was used in your synthesis? Draw the structure, including dashed and wedged bonds, showing the correct absolute configuration (R or S). 

3).Why would NaOH specifically react with 2-methoxyphenyl to generate phenoxide in a solution of ethanol? Could ethanol act as an acid too? Explain.

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A primary goal of organic chemists is to make organic compounds with medicinal properties. In research labs, they work to discover new medicines and in process labs, they work to make known medicines more efficiently: with a higher yield, at a lower cost, or with a lower environmental impact. In this experiment, you'll be synthesizing the over-the-counter cough remedy guaifenesin, known by its trade name Mucinex®. It's an aromatic ether that acts as an expectorant, loosening and thinning bronchial secretions. OH 2-methoxyphenol The carbon atom marked with an asterisk is asymmetric center. When a molecule contains an asymmetric center (*) it can exist as two enantiomers. Guaifenesin exists as a pair of enantiomers: the (S)-(+) enantiomer and the (R)-(-) enantiomer. The (S)-(+) enantiomer is believed to be significantly more biologically active than the (R)-(-) enantiomer, although it's sold as a racemic mixture. 2-methoxyphenoxide OH Guaifenesin OH OH OH OH 3-chloro-1,2-propanediol 2-methoxyphenoxide OH guaifenesin H₂O OH The synthesis of Guaifenesin utilizes the Williamson method (an SN2 reaction mechanism) as the key reaction of a two-part reaction sequence. A primary goal of organic chemists is to make organic compounds with medicinal properties. In research labs, they work to discover new medicines and in process labs, they work to make known medicines more efficiently: with a higher yield, at a lower cost, or with a lower environmental impact. In this experiment, you'll be synthesizing the over-the-counter cough remedy guaifenesin, known by its trade name Mucinex®. It's an aromatic ether that acts as an expectorant, loosening and thinning bronchial secretions. OH 2-methoxyphenol The carbon atom marked with an asterisk is asymmetric center. When a molecule contains an asymmetric center (*) it can exist as two enantiomers. Guaifenesin exists as a pair of enantiomers: the (S)-(+) enantiomer and the (R)-(-) enantiomer. The (S)-(+) enantiomer is believed to be significantly more biologically active than the (R)-(-) enantiomer, although it's sold as a racemic mixture. 2-methoxyphenoxide OH Guaifenesin OH OH OH OH 3-chloro-1,2-propanediol 2-methoxyphenoxide OH guaifenesin H₂O OH The synthesis of Guaifenesin utilizes the Williamson method (an SN2 reaction mechanism) as the key reaction of a two-part reaction sequence.

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