Synthesis of Cholesterol Nonanoate

1. Oct 28, 2009

~Sam~

1. The problem statement, all variables and given/known data

A reaction of nonanoyl chloride with cholesterol to form cholesterol nonanoate, pyridine is also used in the reaction.

1.If a student starts with 0.2543 g of cholesterol, 1.4 mL of pyridine, and 0.14 g of nonanoyl chloride, what would be the theoretical yield of cholesteryl nonanoate?

2.At the end of the experiment, the student isolates 0.2254 g of cholesteryl nonanoate. What is the percent yield for this student’s synthesis?

2. Relevant equations

C9H17ClO + C27H46O -----(C5H5N) -----> C36H62O2 + C5H6NCl- (I believe that is the balance equation, any confirmation?

We are also given:
nonanoyl chloride M.W. = 176.7 g/mol
cholesterol M.W. = 386.6 g/mol
cholesteryl nonanoate M.W. = 527.2 g/mol

3. The attempt at a solution

I might have the solution but I'm not sure. First I believe that they all react with a ratio of 1mol, Using the balanced equation which says that ideally 1 mole of each of the three react together, it shows that C27H46O is the limiting substance as there it least of this. Therefore 1 mole cholesterol makes 1 mole of cholesteryl nonanoate, so 386g of cholesterol makes 526 g of cholesteryl nonanoate, so 0.2543g of cholersterol makes (526/386) x 0.2543 = 0.3465 g of cholesteryl nonanoate, which is the theoretical yield.

For 2) is it just % yield = (0.2254/theoretical yield) x 100

2. Oct 28, 2009

Staff: Mentor

Approach seems to be OK, but I have just skimmed. I haven't checked numbers.

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