Sawhorse method

Visualization of conformers There are four conventional methods for visualization of three-dimensional structures on paper. These are the ball and stick method, the sawhorse method, the wedge and broken line method and the Newman projection method. Using these methods, the staggered and eclipsed conformers of ethane can be drawn as follows. 

Other common methods for representing the three-dimensional structures of molecules include Newman projections for showing conformational relationships and sawhorse figures. Newman projections look down a carbon-carbon bond so that the front carbon, designated by a circle, obscures the carbon directly behind it. Valences (bonds) to the front carbon extend to the center of the circle, while bonds to the rear carbon stop at the circle. Sawhorse projections have the carbon-carbon bond at oblique angles, which attempts to represent a perspective drawing of the molecule. Thus for 2-chloro butane, if one chooses to examine the 2,3 bond, then the sawhorse and Newman projections would be... 

Saccharic acids. See Aldaric acids Saccharin, 997 Salicylic acid, 737 acetylation of, 952 acidity of, 953 synthesis of, 952-954 Samuelsson, Bengt, 1025 Sandmeyer reactions, 892, 894, 906—907, 919 Sanger, Frederick, 1070—1074, 1101—1102 Sanger s reagent. See l-Fluoro-2,4-dinitrobenzene a-Santonin, 1046 Saponification, 794—799 Sawhorse diagrams, 90—91 Saytzeff. See Zaitsev, Alexander M. Schiemann reaction, 892, 893, 905 Schiff s base, 673, 689. See also Imines Schrbdinger, Erwin, 7 Schrbdinger equation. See Wave equation Scientific method, 217... 

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