[greentea11]

Any ideas how I would go from cyclopentanone, to this

https://www.google.co.uk/search?q=2-+phenylcyclohexanene&nfpr=1&source=lnms&tbm=isch&sa=X&ei=yEP5UoqPFuWV7Abfw4AI&ved=0CAgQ_AUoAg&biw=1366&bih=643#q=phenyl%20cyclopentadiene&tbm=isch&facrc=_&imgdii=_&imgrc=lfiNuZ_FDtKIVM%253A%3BNrEqp4rb67x8cM%3Bhttp%253A%252F%252Fwww.ebuychem.com%252Fsmall_pic%252FEBD282376.png%3Bhttp%253A%252F%252Fwww.ebuychem.com%252Fproduct%252F2327-56-2.html%3B120%3B120

(minus one of the double bonds, so essentially 1-phenyl-1-cyclopentadiene

Not sure which mechanism to start out with/whats the easiest way to convert to this, any pointers in the right direction is appreciated so I can get started

[Radu]

 you could use phenyl magnesium bromide, dehydrate and then choose your ideal way of  dehydrogenation. ( Pd/C , for example).

[Benzene]

Any ideas how I would go from cyclopentanone, to this

https://www.google.co.uk/search?q=2-+phenylcyclohexanene&nfpr=1&source=lnms&tbm=isch&sa=X&ei=yEP5UoqPFuWV7Abfw4AI&ved=0CAgQ_AUoAg&biw=1366&bih=643#q=phenyl%20cyclopentadiene&tbm=isch&facrc=_&imgdii=_&imgrc=lfiNuZ_FDtKIVM%253A%3BNrEqp4rb67x8cM%3Bhttp%253A%252F%252Fwww.ebuychem.com%252Fsmall_pic%252FEBD282376.png%3Bhttp%253A%252F%252Fwww.ebuychem.com%252Fproduct%252F2327-56-2.html%3B120%3B120

(minus one of the double bonds, so essentially 1-phenyl-1-cyclopentadiene

Not sure which mechanism to start out with/whats the easiest way to convert to this, any pointers in the right direction is appreciated so I can get started

well you have a carbonyl group and you need to make a carbon-carbon bond, do you know any good ways to do that?

you could use phenyl magnesium bromide, dehydrate and then choose your ideal way of  dehydrogenation. ( Pd/C , for example).

this strategy works, i think, do you understand what he/she means ?

[PhDoc]

Greentea, it's important to start out with a critical analysis of the problem given, keeping in mind one very fundamental rule in organic chemistry - Occam's Razor, i.e. the shortest path is usually the best.

Step one, look at the compound, and realize you need two pieces connected together.
Step two, what bond making and bond breaking synthetic steps will permit you to form the indicated carbon-carbon bond?
f you had your aromatic as a grignard, then what would the identify of the cyclopente system have to be?
What would be the relationship between the keto and end functionalities?
What would the reaction conditions be?
What workup conditions would favor elimination.

Don't memorize this stuff. Those of you who memorize are guaranteed to fail. Please learn to rationalize your way through these problems.

Best of luck.

Dr. Lennox

[greentea11]

Thank you for the tips and help