For example, look at the following series of reactions below. Published by Editorial Staff on | Free download Organic Chemistry As A Second Language – Second Semester Topics (3rd edition) written by David Klein in pdf. You either need to learn how to strategize, or just don’t play chess.
Answer: PROBLEMS For each of the following molecules, count the number of hydrogen atoms connected to each carbon atom. Without this skill, it will be impossible to master even the most basic reactions and concepts.
Hydrogen atoms con- nected to atoms other carbon (such as nitrogen or oxygen) must be drawn: But hydrogen atoms connected to carbon are not drawn. Most students will gain a familiarity with these drawings over time, not realizing how absolutely critical it is to be able to read these drawings ﬂuently.
Clipping is a handy way to collect important slides you want to go back to later. You need to stare at it for a while to see the change that took place.
Most hydrogen atoms are not shown, so bond-line drawings can be drawn very quickly. Imagine thinking that you will keep playing chess, but you just won’t be good at that one aspect of the game. When you start playing your ﬁrst game, you realize that there is quite a bit of strategy involved.
That would be silly, because that one aspect of the game is the whole game itself. After doing this many times, you will get to a point where you do not need to count anymore.
Most strategies in- volve thinking more than just one move in advance. It is not good enough to know only how to move the pieces. Repeat this procedure whenever you have entered ﬁve new reactions. If you keep up with this exercise as the course progresses, you will be in very good shape for solving one-step synthesis problems.
The second half of the course is all about learning reactions and applying them in syntheses. Not only are they easier to draw, but they are easier to read as well. When you see a drawing of a molecule, it is absolutely criti- cal that you can read all of the information contained in that drawing. Organic chemistry | Khan Academy If you’re seeing this message, it means we’re having trouble loading external resources on our website. If you’re behind a web filter, please make sure that the domains * and * are unblocked.
For example, the following compound has 7 carbon atoms: It is a common mistake to forget that the ends of lines represent carbon atoms as well. Don’t be lazy, and don’t think that you can get through the course without learning how to propose syntheses. If you do, you will ﬁnd that your performance in the course will spiral down to a point that will make you very unhappy. Everything that you have learned so far has prepared you for synthesis. Imagine that you are learning how to play chess.
The only way to become proﬁcient at synthesis is to practice. That’s what this chapter is all about. 13.1 ONE-STEP SYNTHESES As we mentioned earlier, one-step syntheses are the ﬁrst synthesis problems you will encounter. You can- not tell yourself that you are not good at synthesis problems, and therefore you will just focus on the other aspects of organic chemistry. Once you get comfortable reading these drawings, you will be better equipped to see the changes taking place in reactions. 1.2 HOW TO DRAW BOND-LINE DRAWINGS Now that we know how to read these drawings, we need to learn how to draw them.
For now, skip forward a few pages. We have some techniques to go over that will help you solve synthesis problems. 334 CHAPTER 13 SYNTHESIS 11. 13.1 ONE-STEP SYNTHESES 335 Remember not to ﬁll in the reagents or the mechanisms. The secret to success in this course is to do a little bit every night (rather than cramming on the night before the exam). Cramming might work well for other courses, but it doesn’t work well in or- ganic chemistry. According to the author; the aim of the fourth edition remains exactly the same as that for the first edition of the book.
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