The two compounds shown to the right have very similar boiling points. Give one reason why we might expect n-propanol to have the higher boiling point, and one reason why we might instead expect 2-pentanone to have the higher boiling point instead.
FO Glyphosate, an herbicide marketed under the trade name Roundup, has received a great deal of press coverage in recent years, and high profile lawsuits regarding the compound provide an example of a case in which the court of law, the court of public 1 opinion, and the best available scientific data have all collided with OH3 1b HO (and arguably diverged from one another (Front. Public Health, 2017, 5, 316). While its health effects can be debated, the molecule is Glyphosate inarguably an interesting test case in protonation states (J. Phys. Chem. A, 2015, 119/21), 5241-9). (50 pts) a) Glyphosate can exist in a variety of protonation states depending the pH of its environment. Predict the ordering of the pka values for the four labelled protons in the given structure. Note that protons la and 1b are initially equivalent and so may be lost in either order, however these first and second protons of the phosphonate group do not appear adjacent to one another in the pKa sequence. Explain why you ranked the pka values in the order you did, including justifying why la and 1b are not next to each other. b) Give the hybridization state and the expected molecular geometry for each of the three atoms marked with an asterisk: P, N and C. c) The pka values of the various functional groups in glyphosate are so far apart that the molecule normally exists as a zwitterion (a molecule with both positive and negatively charged atomic centers). We can view the formation of this zwitterion from the neutral structure as an intramolecular proton transfer reaction (a reaction in which the acid and the base are part of the same molecule). Redraw the structure below, filling in all omitted lone pairs, and draw the mechanistic arrows representing this intramolecular acid-base exchange (keeping in mind which proton you expect to be the most acidic and which part of the molecule is likely to be an effective base). Then draw the zwitterionic product of this proton transfer. du d) The proton transfer in partc is a spontaneous process at neutral pH, and equilibration occurs at an extremely fast rate. Draw a qualitatively accurate free energy diagram for this process, labelling the axes, products and reactants, Arxn and Eq. e) While glyphosate has a particular pka profile, we can consider strategies for synthesizing similar molecules in which the ordering of the pka values is altered in some way. One potential way to do this would be to keep the same general structure but replace some of the alkane hydrogens with other atoms. On the structure of glyphosate in partc explicitly add all omitted hydrogen atoms and number them (H1, H2, etc.). If you wanted to create a variant in which the acidity of the carboxylic acid group was similar to that of glyphosate, but the phosphonate group had its acidity significantly enhanced, which of the hydrogen atoms you indicated would you replace, and what would you replace them with? Explain your choices to receive full credit
