1 The Diels-Alder reaction is a conjugate addition reaction of a conjugated diene to an alkene (the dienophile) to produce a cyclohexene. 2  The simplest example is the reaction of 1,3-butadiene with ethene to form cyclohexene:3  The analogous reaction of 1,3-butadiene with ethyne to form 1,4-cyclohexadiene is also known: Due to the high degree of regio-and stereoselectivity (due to the concerted mechanism), the Diels-Alder reaction is a very powerful reaction and is widely used in synthetic organic chemistry.
Best Answer: Buyers have up 7 days to pay for an item before you as a seller can open an unpaid item case with ebay. They have a whole process they ask that sellers follow: Buyers automatically enter into a legally binding contract to purchase the item from the seller if they win an online auction or use the Buy It Now feature.
Ending your auction at the right time is important. Generally, the best time to end an ebay auction is from 6-11pm EST. A normal ebay auction runs for 7 days. So, if you start it on a Tuesday at 5:00am, it will end the next Tuesday at 5:00am. You can schedule it to go live in advance for a small fee.