synthesis+wiki

The purpose of this exercise is to take what you have learned to the next level, and bring together the many reactions that you have learned to build creative synthetic strategies. An equally important goal is to develop the skills of creative cooperation in this endeavor. Organic chemists seldom work alone, but rather consult with each other to determine what weaknesses a plan may have before setting out on a multi step synthesis, and to determine alternative synthetic strategies in case a planned step does not provide the expected product. There are a few rules that we need to follow in order to maintain a high standard and to give each class member the best opportunity to make contributions. These are: 1) A maximum of 3 people can sign up for any one molecule 2) Between now and April11, you may sign up for only one molecule. This gives all class members a chance to take part in this project. If you have ideas about another molecule, you may message the people that are working on that molecule to share your ideas, but please refrain from posting synthetic schemes on another molecule to give them a chance to figure it out. 3) After April 11, you can sign up for any molecule that is still available. Any work that you do counts for extra credit up to a maximum of 100 points. 4) If you do not post anything on the prolem within 1 week of signing up for it, your name may be taken off of the list, and another person's put up. 5) Each person that signs up for a molecule should submit at least one retrosynthetic analysis (disconnection) (see Wade, pages 372 through 374). 6) All reactions that are proposed should be accompanied by a page reference to a book journal article or web page (with web pages pay attention to papers referenced in that page. If there are none, be suspicious of the information there.) The reference should contain sufficient information for a reader to find the exact page of that book or journal article where that reaction can be found. 7) At least one reference should be to a source other than Wade. 8) Carbon limits on starting materials do not apply to reagents that do not contribute carbon atoms to the target molecule, for example, triphenyl phosphene or Sia-Borane can be used even if the carbon limit is two or six.

**Great website that allows you to find reactions by specifying the product and the reactant:** WebReactions

These are all the rules. My suggestion is to post frequently and create a lively dialogue on the synthetic strategy. Design of an organic synthesis, like any other creative endeavor, does not happen in a single step, but is rather a process of thinking, writing, rethinking, and rewriting. You will be graded, not on whether you come up with the perfect synthesis in one try, but rather on the quantity and quality of your contributions. You can always respond and re-work your strategy according to the suggestions of others. I will comment on the proposed synthesese as much as possible, to give you a chance to work out the bugs. For this reason it is important to post early and often, not to wait until the last minute Remember that there is more than one correct synthesis, just as there are many incorrect ones. In evaluating alternatives, take into account that the best synthesis 1) minimizes the number of steps, 2) has reactions that yield predominantly the desired product, with a minimum of side products, 3) subsequent reactions do not affect the desired functional groups placed by previous reactions (i.e. the most labile functional groups are placed last). When you see something that you would like to work on, Click "edit" in upper right. Put your name down, and click "Save". Then click the blue link in the bottom of that text section. This will take you to the page of that molecule. You can also click the link from the home page. You make changes in the molecule page the same way. To insert pictures you first need to upload them from your computer. Do this by clicking on the picture above, beside the TV set. Then click on the upload tab. Good luck :-)

here is the hyperlink for[| chemsketch]
 * Chemsketch download**

compound1 This molecule is an exercise in alkene chemistry that I made up. Devise a synthesis from any compound containing 3 carbons or less. Sign up: Gloria Tucker, Lydia Owusu, Jason DeMao

compound2 This synthesis is a good exercise in alkyn chemistry. Make it from any compound containing 2 carbons or less. Sign up:Katalin Sagi, {Shaun Alvarado, Alex Kravetz [extra credit]}

y compound3 This compound and the next one are exercises in the synthesis of cyclopropyl rings. Make this one from any starting materials having 3 carbons or less. Sign up: Shaun Alvarado, Alex Kravetz, Katalin Sagi(extra credit)

compound4 Make a racemic mixture of just these stereoisomers (no trans) from any starting materials having 3 carbons or less. Sign up: __**ALFRED RUSH OLATUBOSUN O OJEKUNLE**__ __**SANAZ ALISHAHDANI**__

Alfred Rush

compound 5 Here is more practice making alkenes. Make this compound from any starting materials having 2 carbons or less. Do you remember a reaction that forms carbon-carbon double bonds directly? Sign up: Jingwen Huang, Chaz Baldwin, Elein Ravelo

tremorine Here is some shaky chemistry. Tremorine is a drug given to laboratory animals to induce the sympthoms of parkinsonism for research on that disease. Make this compound from starting materials containing 2 carbons or fewer. you may need to look up some amine reactions to make the rings. Sign up: Priscila Ronqui, Ryan Carbaugh,Katalin Sagi (extra credit), Alfred Rush (Extra Credit) meparfynol Relax! Meparfynol is a seditive and hypnotic. Make this molecule from any starting materials that contain 2 carbons or less. But save it until after finals! Sign up: Meaghan Bartlett, April Weliever, Priscila Ronqui (extra credit)

pyrethrine Here is the more interesting piece of another natural insecticide, pyrethrin. This compound is produced by the chrysanthemum plant. Variations of this type of molecule are used in many commercially available insecticide formulae, because they have low toxicity to mammals and other higher animals, and they are biodegradable. Make a racemic mixture of this pair of enantiomers from any compounds containing 6 carbons or less, that are readily available from the Sigma Aldrich catalog. [] Sign up: Jingwen Huang (extra credit), Miranda Maestrelli, Jenny Saravia



linolenic acid Linolenic acid is one of the famous omega fatty acids that have been found to have beneficial health effects, such as reducing triglycerides and lowering blood pressure. Make this compound from any compound containing 8 carbons or less, that is readily available from Sigma-Aldrich [] Sign up Meaghan Bartlett (extra credit), April Weliever (extra credit), Ryan Carbaugh (Extra Credit)

kinoprene Kinoprene is an insect hormone. Derivatives of this type of compound have the potential of being highly selective, and non toxic (to us and non target animals) insectisides. Research in this area may bring about a new "green revolution", Make this molecule from any starting materials that are readily available from the Sigma Aldrich catalog [] Sign up: Kerri Brinegar, Carlos Avila, Calypso Dogbe

pentacosadiynoic acid Monomers based on pentacosa-10,12-diynoic acid can be polymerized to make a highly conjugated poly-alkene called 'polydiacetlylene'. This polymer has some interesting properties. It is colored and fluorescent, and the absorption and emission spectra can be changed if the polymer chain is physically deformed. When these polymers are conjugated to functional groups that specifically bind certain molecules or ions, it can be a sensor for thos molecules or ions. NASA has also experimented with growing uniform crystals of polydiacetylene to serve as entirely photonic logic chips. Devise a synthesis of this compound from any starting material of 12 carbons or less that is available in the sigma aldrich catalog. [] Sign up: Kerri Brinegar (EC), Carlos Avila (EC), Calypso Dogbe

Below is an example of the former use, depicted in advanced materials: Here is a good review on polydiacetylenes: