[Sofire]

Hey, I've got some questions for a chem assignment that I hope someone will be able to help me with and also if you can explain why this is so it would be of a great help as I have an exam coming up for this in a week (eek). Thanks.
Q: What organic product would you expect from the reaction of ethylmagnesium bromide (CH₃CH₂MgBr) with benzaldehyde (C₆H₅COH) and then hydronium (H₃O⁺)?

[azmanam]

start here:

http://www.cem.msu.edu/~reusch/VirtTxtJml/aldket1.htm#rx2b

[jpg28]

Generally, Alkyl Magnesium Bromides (like the one you gave, that is, ethyl magnesium bromide) are known as Grignard reagents, and act as strong nucleophiles (could also be strong bases). You have an electrophile, which in this case is benzaldehyde that has an electrophilic (electron-loving) carbon atom that is part of the carbonyl group. The CH₃-CH₂: ^- carbanion then adds to the carbonyl, thereby pushing the pi-electrons to the oxygen atom to create an alkoxide (this leaves your oxygen atom with a negative charge). The electrons on the oxygen atom then attacks one of the hydrogen atoms in the hydronium ion (H₃O⁺) and gives off water.

The final products, therefore, are 1-phenylpropanol and H₂O. I hope that helped you understand. Have a nice day.