Аллилбензол - из бензола, аллилового спирта и глины К-10.

Synthesis of 1-Arylalk-2-enes and 1-Arylalkanes via Friedel-Crafts Alkylation with Allylic Alcohols Catalysed by an acidic Clay
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ArH + C5H11-CH=CH-CH2OH ---(K10)---> C5H11-CH=CH-CH2-Ar + H2O [A]

ArH + C5H11-CH(OH)-CH=CH2 --(K10)--> same as above [B]

96mg K10 acid clay and 7.5ml toluene were refluxed and a solution of octenol(320mg, 2.5mmol in 5ml toluene, isomer [A] or [B]) was added over a few minutes with stirring, followed by a further 5 mins at reflux. Conversion and yieldwere detected by GC. Octenol converted 100%, yield 89%[A] or 79%[B].

Syntheses of products with K10 as catalyst (ratio alcohol : catalyst 1:2;reaction time 5min for each case)
Ar..........T/°C....Yield(a)..Ratio o:m (b)
Ph...........80.......80...........---..... MeC6H4......111.......94.........46:5:49...
EtC6H4......111.......80(c)......42:4:54...
iPrC6H4.....111.......70(c)......36:0:64...
tBuC6H4.....111.......83(c)......24:0:76...
FC6H4........85.......43.........16:0:84...
MeOC6H4.....111.......92(c)......55:0:45...

(a) isolated yield
(b) determined by GC
(c) the K10 was not dried prior to use in these cases

The amount of catalyst could be reduced to a mass ratio of octenol:K10 of ca. 1:0.05 by using longer reaction time(1h), but yield was lower. Drying of the catalyst produced somewhat better yields.

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