Question

Synthesis of cinnamic acid experiment's chemical equation (Knovenagel reaction) is shown below:

C₇H₆O    +    C₃H₄O₄    ---->    C₉H₈O₂    +    CO₂ + H₂O

benzaldehyde + malonic acid ----> cinnamic acid + carbon dioxide + water

Following table shows the amount of each compounded needed:

Reagents	Amounts (in g or mL)	Amounts (in mmol)	Molar Equivalents
Benzaldehyde	1.5 mL
Malonic Acid	2.3 g
Piperidine	2.3 mL

Fill in the rest of the table. (molar equivalents: the ratio of moles of reagent to moles of the main organic starting material, benzaldehyde)

Answer 1

Density of benzaldehyde = 1.04 g/mL

Mass of benzaldehyde = 1.04*1.5 = 1.56 g

Molecular weight of benzaldehyde = 106.121 g/mol

Moles of benzaldehyde = 1.56/106.121 = 0.0147 moles = 1.47*10^-5 mmoles

Molecular weight of malonic acid = 104.0615 g/mol

Moles = 2.3/104.0615 = 0.0221 moles = 2.21*10^-5 mmoles

Density of piperidine = 0.862 g/mL

Mass = 0.862*2.3 = 1.9826 g

Molecular weight = 85.15 g/mol

Moles = 1.9826/85.15 = 0.02328 Moles = 2.328*10^-5 mmoles

Molar equivalents of benzaldehyde = (1.47/1.47 )= 1

Molar equivalents of malonic = 2.21/1.47 = 1.50