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FC alkylation with oxiranes vs. aziridines

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Rhodium:
Friedel-Crafts alkylation of benzene only gives 2-phenyl-1-propanol and no 1-phenyl-2-propanol (P2Pol), this in contrast to the same reaction between benzene and propyleneimine (2-methyl-aziridine), which depending on the reaction conditions gives different ratios between 2-phenyl-2-aminopropane and 1-phenyl-2-aminopropane (amphetamine). The reaction of aziridine with substituted benzenes give moderate yields of phenethylamines.

Friedel Crafts Reactions of Three-Member Heterocycles I. Reaction of Propylene Oxide with Benzene
Norman Milstein
J. Het. Chem. 5, 337-338 (1968) (https://www.thevespiary.org/rhodium/Rhodium/pdf/friedel-craft.oxirane.pdf)

Abstract
The Friedel Crafts reaction of propylene oxide with benzene has been reinvestigated, and under anhydrous conditions the product is 2-phenyl-1-propanol.
____ ___ __ _

Friedel Crafts Reactions of Three-Member Heterocycles II. Alkylation of Aromatic Compounds with Aziridines
Norman Milstein
J. Het. Chem. 5, 339-341 (1968) (https://www.thevespiary.org/rhodium/Rhodium/pdf/friedel-craft.aziridine.pdf)

Abstract
The Friedel Crafts reaction of propylenimine with symmetrical arenes in the presence of aluminum chloride was investigated. Electron donating substituents increase the alpha-methyl-beta-phenethylamine/beta-methyl-beta-phenethylamine ratio, while increasing the temperature has the opposite effect. In the reaction of chlorobenzene or toluene with aziridine, the nature of the substituent has little effect on the ortho/para ratio.

josef_k:
Friedel-Crafts alkylation of benzene only gives 2-phenyl-2-propanol and no 1-phenyl-2-propanol (P2Pol)

But our russian comrades found a way (or is that a bunk patent?)
Post 310648 (missing) (Chemikaze: "Translation", Russian HyperLab)

Rhodium:
It seems like the Russians have managed to circumvent the problem mentioned in the article above - that the propylene oxide is hydrolyzed before the alkylation takes place - by blowing dry helium gas through the reaction mixture to carry away any formed HCl.

Intact propylene oxide complexed with AlCl3 is alkylated by benzene in the least hindered position, yielding 1-phenyl-2-propanol.

If the propylene oxide first undergoes acid-catalyzed ring-opening, an isopropylic carbocation (carbonium ion) forms, which then attacks the benzene to form 2-phenyl-1-propanol.

So - by eliminating protic acids from the reaction mixture, the epoxide stays intact, and the more interesting of the isomeric alcohols can form. This is probably the explanation for the patent mentioning that "During this reaction HCl gas evolves, leading to low yields and an impure product, therefore He gas is allowed to flow through the reaction mixture."

yinga:
Friedel-Crafts alkylation of benzene only gives 2-phenyl-2-propanol
--- End quote ---

Should this be 2-phenylpropanol?

Friedel-Crafts alkylation of benzene only gives 2-phenyl-2-propanol and no 1-phenyl-2-propanol (P2Pol),
--- End quote ---

Doesn't it sometimes give the 1-phenyl-2-propanol (up to 41% in the article)?  It was only reported to give exclusively the primary alcohol in one of the references and under the "strictly anhydrous" conditions of the reported experiment.  And then the translated patent above claims it gives the 1-phenyl also (not under anhydrous conditions).

Rhodium:
Should this be 2-phenylpropanol?

Yes, or more precisely 2-phenyl-1-propanol. I have edited my typos above.

Doesn't it sometimes give the 1-phenyl-2-propanol (up to 41% in the article)?

I'm just quoting their abstract. And as we can see ourselves by comparing the article and the russian patent, different experimental techniques gives different end products in the same general reactions.

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