Appendix Isopropyl Alcohol

Make determinations in triplicate on the flash point of standard p-xylene and of standard isopropyl alcohol which meet specifications set forth in Appendix A2. Average these values for each compound. If the difference between the values for these two compounds is less than 15 F (8.5 C) or more than 27 F (l6 C), repeat the determinations or obtain fresh standards (Note 7)... 

Procedure (See Chromatoghaphy, Appendix IIA.) Inject about 5 xL of the Mixed Standard Solution into a suitable gas chromatograph equipped with a flame-ionization detector and a 1.8-m x 3.2-mm stainless steel column, or equivalent, packed with 80- to 100-mesh Porapak QS, or equivalent. Maintain the column at 165°. Set the temperature of both the injection port and the detector to 200°. Use helium as the carrier gas, flowing at 80 mL/min. The retention time of isopropyl alcohol is about 2 min, and that of ferf-butyl alcohol is about 3 min. 

Liu (2007) introduced another method called soap extraction to quantify acid number. Because the anionic surfactant can be accurately determined by potentiometric titration (see Appendix A in Liu, 2007) with benzethonium chloride (hyamine 1622), it is reasonable to use this method to find the natural soap amount. Because this potentiometric titration is for the aqueous phase, the soap should be extracted into the aqueous phase as the first step. As an anionic surfactant, the natural soap may stay in the oleic phase and form Winsor type 11 microemulsion when the electrolyte strength is high. To extract the soap into the aqueous phase, NaOH is used to keep the pH high with low electrolyte strength. Also, isopropyl alcohol is added to make the system hydrophilic so that soap will partition into the aqueous phase. 

For the isopropyl alcohol to acetone process flowsheet given in Appendix B, Figure B.10.1. list the 2 minimum input information required to obtain mass and energy balances for this process. Using the process simulator available to you, simulate the isopropyl alcohol to acetone process, and compare your results to those given in Table B.10.1. 

For this library, we chose to use three types of isocyanates (neutral, electron rich, and electron deficient) to demonstrate the broad utility of the urea-formation reactions. Employing the above strategy and using the split-and-pool approach, we synthesized a 27-membered urea library with purities ranging from 95 to 99%. All the compounds prepared were characterized by 1FI NMR and mass spectroscopy. Acetonitrile can also be used as a substitute for DCM, but lower yields and product purities are generally observed. Attempts to use other protic solvents, such as isopropyl and ethyl alcohol, were unsuccessful. The best results were achieved when a chlorinated solvent (DCM) was used. The structure identity of all products was confirmed by 1FI NMR and MS spectroscopy. Expected molecular ions (M + Na+) were observed for all the products, and in all cases as the base peak. The compounds and yields are listed in Appendix 3.1. 

With structurally similar formate esters, the ratio is ethyl/isopropyl/l-butyl formate = 1/55/4570 at 650 °K. If charge polarization was in the usual direction, C-1 would be a 5 -charge center. Alkyl substitution at that center would therefore stabilize the transition states and significantly accelerate reaction rates. Since it is possible to account for almost all of the observed rate increase per methyl substituent at C-1 in terms of gauche destabilizations of the alcohol ground states (see appendix), it would appear that charge polarization in the transition states of these reactions is almost negligible. 

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