SEPS

C or a part of C is put in a sep. funnel wich is connected to flask containing B ( wich can be a bottle), and a tube connect this flask to the bubbler into flask containing A, wich have other tube to redirect No and nitrite gases. Flask A is in water bath to keep rxn temp between 20 - 30 C /reaction is slightly exothermic) and stired magnetically. MeONO is bubbled in A with a bubbler that provides little bubbles (not necessary a gas difusor, but a single tube is not enough, you must increase then B and C). Bubbler is all deep as it is possible. 

We start rxn, one drop / second or so C in B. Sometimes we close sep funnel and shake flask B to ensure a constant rate of MeONO generation. Addition speed is limited by equilibrium of pressure between flasks. If it is too much quick, then MeONO gas go through sep. funnel, then we close the sep funnel and wait a bit till generation is low. The addition of C in B takes 1 hour, we close sep funnel and shake a bit B to finish reaction. If rxn (A) climbs temp too much, we can add ice in the water bath. I ve monitorized temp touching a part of solution that was out of water bath. At the final part may be water is to much cool, so we can take it out. After the addition of C in B we wait one more hour. 

This procedure has been tested for a lot of bees and conditions are similar. Displl solvent and distill ketone with a water pump. My yield, 41 grams, about 75 %. Scaling. Of course. This procedure have been done with 150 cc of safrol, but with T75 I of methanol with simiair yields, so I ve prefered to present this version wich is better (less solvent, less time) Addition of nitrite i/vas done in 2,5 hours. When scaling, water in B can be decreased if we have problems with our volume flasks, but this means a lot of NaN02 is not dissolved, so each 15 minutes, we close sep. funnel, and shake B a bit, and when there is no foam, we can open sep. funnel again (1 drop or abit more /second). My opinion is 150 is ok, but theorically you can scale more. More time rxn is not a problem for product. 

Hazards. If you add two much, quickly C in B, MeONO goes through sep. funnel. So close the key, but if there w/as too much addition or you shake immediatly then generation is higher than the possibilities of bubbler, and rubber on flask B can jump with a lot of foam and solution. For this reason it s better to have NaN02 dissolved, to prevent surprises, but it s not necessary. Be patient and shake. Don t forget redirect NO and MeONO fumes out to the window. 

So if one were to replace sec-butyl alcohol in the recipe above with an equimolar amount of safrole in the above reaction, Strike will wager that a positive bromination experience will occur. And all this using the very common 48% aq. HBr The oniy difference being that once the reaction mix had cooled, one should do either of two things (1) distill as described except the bromosafrole will be the last thing to come over (not the first), or (2) flood the reaction mix with water to bring the product out of solution after which it can be physically separated by decanting or sep funnel or some such shit. 

After a couple of hours you may notice that what s coming over contains less oil, and eventually no oil at all. Just water. That s it, you ve done it. The benzodioxole will form a layer underneath the water. We just need to separate the oil with a sep funnel, wash with water twice, to remove any traces of milkiness, which I think... 

After an hour we pour the contents into 500ml of water. We then separate with a sep funnel and extract the water layer with 50ml of clean ether. We combine these two ether layers and dry over sodium suiphate. 

A dry reflux set-up is used with a three neck flask allowing a thermometer and sep funnel to be attached to the reaction flask. The thermometer is placed well below the surface of the flask contents. If the temperature rises above 55°C ice will need to be used to cool things down a bit So the three neck flask will be sitting in an ice bath on the stir plate before we begin. If ether is used instead of THF the ether will boil well before 50°C is reached giving a better indication of how hot things are getting. 

THF into the sep funnel. It is recommended that an iodine crystal is placed in the reaction flask and before the condenser is attached, nitrogen should be blown Into the receiving flask to remove any air. As / didn t have any nitrogen available I skipped this step but I did place one small crystal of iodine into the reaction flask. When the iodine is added the solvent will begin to turn brown. Although this looks like the iodine is just dissolving it would appear from what I have read that this is also caused by the reaction. 

Safrole from the Grignard reagent Keeping the apparatus from the above reaction, pour 60g of allylbromide into the sep funnel. As with the ingredients of the last procedure the allylbromide must be dried over sodium sulphate. This stuff is really nasty, use a mask at least or a fume cupboard if you can get access to one or fill the sep funnel outdoors. The fumes are invisible and pretty lethal -please be warned. 

Nonbonded interactions are the forces be tween atoms that aren t bonded to one another they may be either attractive or repulsive It often happens that the shape of a molecule may cause two atoms to be close in space even though they are sep arated from each other by many bonds Induced dipole/induced dipole interactions make van der Waals forces in alkanes weakly attractive at most distances but when two atoms are closer to each other than the sum of their van der Waals radii nuclear-nuclear and electron-electron repulsive forces between them dominate the fvan derwaais term The resulting destabilization is called van der Waals strain... 

Because alkyl halides are insoluble m water a mixture of an alkyl halide and water sep arates into two layers When the alkyl halide is a fluoride or chloride it is the upper layer and water is the lower The situation is reversed when the alkyl halide is a bro mide or an iodide In these cases the alkyl halide is the lower layer Polyhalogenation increases the density The compounds CH2CI2 CHCI3 and CCLi for example are all more dense than water... 

Occasionally an optically inactive sample of tartaric acid was obtained Pasteur noticed that the sodium ammonium salt of optically inactive tartaric acid was a mixture of two mirror image crystal forms With microscope and tweezers Pasteur carefully sep arated the two He found that one kind of crystal (m aqueous solution) was dextrorota tory whereas the mirror image crystals rotated the plane of polarized light an equal amount but were levorotatory... 

The nonplanarity of allenes has an interesting stereochemical consequence 1 3 Disubstituted allenes are chiral they are not superimposable on their mirror images Even an allene as simple as 2 3 pentadiene (CH3CH=C=CHCH3) has been obtained as sep arate enantiomers... 

Although GGMS is the most widely used ana lytical method that combines a chromatographic sep aration with the identification power of mass spectrometry it is not the only one Chemists have coupled mass spectrometers to most of the mstru ments that are used to separate mixtures Perhaps the ultimate is mass spectrometry/mass spectrome try (MS/MS) m which one mass spectrometer gener ates and separates the molecular ions of the components of a mixture and a second mass spec trometer examines their fragmentation patterns ... 

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