The Vespiary

If one requires high concentration HNO3 for a single nitration step and doesnt want to mess with distilling such an unforgiving chemical-- how would he go about determining a particular concentration when extracting with DCM?  Considering he has 100ml of the 70% stuff mixed with 100ml conc. H2SO4..How much of the pure stuff can be expected to extract into 200ml of DCM??  What is the minimum and upper limit of DCM to solvate all the nitric in this particular example? Can someone reference the original patent maybe??

My guess is nothing. Iff you want to nitrate in DCM use HNO3/Silicagel. (1 part 70% HNO3/3 part Silica)

Ever checked my page?

Aromatic Nitration with KNO₃/H₂SO₄ in Dichloromethane

Tetrahedron Letters, Vol 42(7), 1387-1389 (2001) (https://www.thevespiary.org/rhodium/Rhodium/chemistry/aromatic.nitration.html)

(https://www.thevespiary.org/rhodium/Rhodium/chemistry/aromatic.nitration.html)

Abstract

Pure dry HNO₃ can be liberated from KNO₃ with 96% H₂SO₄ directly into CH₂Cl₂ to yield solutions of variable concentration for use in a number of organic reactions. The present method efficiently replaces the employment of 100% HNO₃ in some synthetic applications, avoiding the problems associated in storage and handling the acid.



Nitration Of Phenols Under Mild And Heterogeneous Conditions

Molecules 2001, 6, 614-620 (https://www.thevespiary.org/rhodium/Rhodium/pdf/phenol.nitration.pdf)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/phenol.nitration.pdf)

Abstract

Nitrophenols can be obtained in moderate to high yields using a combination of Mg(HSO₄)₂ or NaHSO₄.H₂O, NaNO₃ and wet SiO₂ in dichloromethane at room temperature.

Thanks Rhod..

I found the original patent:

Patent US3981975 (http://l2.espacenet.com/dips/viewer?PN=US3981975&CY=gb&LG=en&DB=EPD)

Says in a 53ml HNO3/47ml HSO4 lot..3x100ml DCM extractions will extract 59.3% HNO3 (or 31.2 grams).

Nitration of Aromatic Compounds on Silica Sulfuric Acid
Mohammad Ali Zolfigol, BiBi Fatemeh Mirjalili, Abdolhamid Bamoniri, Mohammad Ali Karimi Zarchi, Amin Zarei, Leila Khazdooz, and Jalil Noei
Bull. Korean Chem. Soc. 2004, 25 (9), 1414-1416

(https://www.thevespiary.org/rhodium/Rhodium/hive/hiveboard/picproxie_imgs/pdf.gif)

Preparation of silica sulfuric acid can be found in

Post 475011 (https://www.thevespiary.org/talk/index.php?topic=7374.msg47501100#msg47501100)

(demorol: "Silica sulfuric acid/KBrO3 Oxidation of Alcohols", Chemistry Discourse)