t-Alkyl Groups. I. Orientation of t-Alkylation Products of Toluene and Ethylbenzene

Minimizing Isobutylene Emissions from Large Scaletert-Butoxycarbonyl Deprotections

“…When taken in conjunction with the fact that isobutylene emissions from dichloromethane and toluene were relatively low (Table ), it became apparent that another process was also occurring. In the case of toluene, formation of at least some 4- tert -butyltoluene was expected; 8a, however, GC analysis indicated that this accounted for at most 5% of the isobutylene. Instead, it was determined that, under the reaction conditions, the cationic polymerization of isobutylene 11,15 to form nonvolatile oligomers was in fact responsible for the observed low emissions (Scheme )…”

NITRO MUSKS. III.1 ASYMMETRICAL MUSKS OF THE DINITRO-tert-BUTYL-m-XYLENE SERIES

“…In our work with the musks we have noted frequent instances of the extreme adversión of the feri-butyl group to entry in a position ortho to a methyl group in the benzene nucleus: the butylation of m-xylene leads exclusively to the symmetrical isomer; the teri-butyl group enters p-cymene almost exclusively ortho to isopropyl rather than to methyl; butylation of toluene gives predominately para, together with some meta (14); the /erf-butyl group enters m-cresol methyl ether in position para to methyl; butylation of pseudocumene by the Friedel-Crafts reaction results in the migration of methyl group from a position ortho to tertbutyl with production of sym-teri-butylhemimellitene; the teri-butylation of mesitylene has not yet been accomplished. The failure of the above-mentioned attempt to prepare iert-butylpseudocumene by reacting the lithium compound of XXIII with dimethyl sulfate suggests that the same adversión obtains regardless of the order of entry of the two groups.…”

Production of tert-Butyltoluene by Depolyalkylation

“…Production of fort-butyl aromatics has been the subject of several reviews. The latest (9) compares various alkylating agents, including diisobutylene, and many different catalysts. Use of hydrofluoric acid was reported in 1939 (7).…”