Session Start: Sun Jul 15 11:42:42 2007 Session Ident: #Chemistry [11:42] * Now talking in #Chemistry [11:42] * beta.PilotAge.com sets mode: +nt [17:21] * DrSturm has joined #Chemistry [17:21] * DrSturm has left #Chemistry [17:23] * DrSturm has joined #Chemistry [18:55] * caligirl has joined #Chemistry [18:56] Hey [18:56] I have some questions [18:57] O.K. [18:58] alright so I'm a little confused about when we see resonance structures [18:58] for any of the new synthesis/reactions we've looked at [19:00] For EAS it is only important to know the "hybrid" resonance structure as that is the one used in the mechanisms [19:01] so we'd only need to show resonance structures if you asked us for a detailed mechanism? [19:01] and according to the study guide you may have to draw nitration or halogenation [19:02] No, yu would need to show them if I asked specifically for resonance structures or show the "hybrid" structure on a mechanism [19:03] The study guide doesn't mention drawing resonance structures so you can assume it won't be asked. [19:03] so do the resonance hybrid resonance structures occur in every EAS? [19:03] sorry *hybrid resonance [19:03] Yes. [19:04] oh so we don't need to worry about resonance for the test then? [19:04] other than as it applies to halogenation or nitration [19:04] oh ok [19:04] thanks [19:04] and I have one more question [19:05] in an alkenylbenzene reaction, when CH2N2 and heat is added, I was a little confused about the resulting product [19:06] Addition of a carbene, check Alkene, Reactions in the CHE 300 Review [19:06] on the notes it just has the ring and then a triangle coming off of it but it didn't have the CH2 in the triangle [19:07] like i know what it would look like for a normal alkene reaction [19:07] but it looked different in the example given for the CH2N2 addition to alkenylbenzene [19:07] intersecting line are assumed to be -CH2- or methylenes [19:08] oh ok so the attached CH2 is just assumed to be there as part of the triangle [19:08] ? [19:09] Follow the strutcure of the starting material and re-draw the product as a condensed structure rather than a line drawing [19:09] wait what? [19:10] In the notes just re-draw the product shown. [19:10] The starting material is shown as a condensed formula and the product as a line drawing [19:11] oh ok [19:11] with the methyl group coming off [19:11] and then the other two methyl groups included in the triangle [19:12] Then instead of a "trinagle" you will show the -CH2- [19:12] with the last added CH2 is the bottom point of the triangle [19:12] ok [19:12] that makes sense now [19:12] thank you! [19:13] Yes, the point on the triangle [19:14] * caligirl has quit IRC (Leaving) [19:28] * DrSturm has quit IRC [19:28] * Disconnected Session Close: Sun Jul 15 19:28:17 2007