Tetralins, alkyl-substituted

The results in Figure 1 can be interpreted in terms of general ring structures with the hydrocarbon classes. The peak for the polypolar aromatic fraction at 160° C probably is caused by polar-monocyclic compounds and the peak at 240° C is probably the result of polar dicyclic compounds. The broad curve in the monoaromatics centering at 275°C is probably mainly caused by alkyl-substituted tetralins while the peaks... 

A range of diols and cyclic ethers were used to carry out alkylation of aromatics (benzene, toluene, xylenes, trimethylbenzenes, naphthalene) in the presence of triflic acid.204 310 In a recent study,311 various methyl-substituted benzene derivatives were alkylated with 1,4-diols [Eq. (5.117)] to form substituted tetralin derivatives in high yields. The transformations involve an intermolecular alkylation step followed by intramolecular alkylation (cyclialkylation). 2,2,5,5-Tetramethyltetrahydrofuran is similarly effective. For example, it alkylates benzene to give octamethyloctahydroan-thracene (98% yield) and reacts with naphthalene to yield octamethyloctahydrote-tracene [Eq. (5.118)]. 

Friedel-Crafts alkylations. 1 -Substituted tetralins are obtained from cyclic ethers such as 2-(3-arylpropyl)tetrahydrofurans and alkyl Al-(l-hydroxy-4-arylbutyl) carbamates by treatment with TiCl. ... 

Aromatic compounds such as short (Cj, n=l, 2, 3) alkyl substituted benzenes occur at component (d) (280 C), with longer chain (C, n=5, 6, 7) benzenes + tetralins at 320 component (e). Component (f) at 0 is thought to represent CjjH2n-10 series. Naphthalenes are found at component (g) (30 ) and acenaphthene/biphenyl ions are present at component (h) (50 ,... 

Samples 8 and 9 had associated components from both MS and CMR in CV3 and CV4. Fragment ions m/z 145, 159 and 173 loaded moderately in this space, as did the CMR variable 142 ppm. These are not inconsistent with the interpretation of indane/tetralin found in the CVl + CV2 space. Sample 10 had associated variables of m/z 142 and 156, C] and C2 alkyl substituted naphthalenes and an "acenaphthene/biphenyl" (m/z 144, 158...) component. The lone variable from CMR, at 131 ppm, might arise from either of these components (2 methyl naphthalene 131.7 ppm or acenaphthene 131.5 ppm CDCI3) considering that we chose variables as virtually + 1 ppm. 

Steric and electronic effects in the chromic acid oxidation of 17 mono- and polyalkyl-substituted tetralins have been fully examined. As perhaps expected, preferential oxidation occurs at benzylic methylene position (s) para to the alkyl substituent in the benzene ring. 

When there was Me (alkyl) substitution at C3 (with the exception of formation of a tertiary carbocation at the 4th carbon from the cyclizing ring—for example, see conversion of 31 into 30), then both the indane and tetralin were formed. Many of these experiments were later repeated by Kalif and Roberts who also reported the cyclization of 1-phenyl 3- or 4-Me-substituted pentanols with H2SO4. For these cyclizations, the formation of the tetralin predominated over the formation of the indane. ... 

THF-soluble, pentane-insoluble products from the thermal dissolution of Kaiparowitz coal in tetralin comprise most of the soluble products. These materials are highly aromatic with a carbon aromaticity of about 70%. The aromatic portions are on the average highly substituted, possessing roughly one oxygen, 2.2 aryl or alkyl substituents, and 2.6 hydro-... 

In the 1950s, a new class of musks was discovered, the polycyclic musks. These materials mostly have indane, tetralin or isochroman structures, heavily substituted by methyl or other small alkyl groups. Typical members of this family are Traseolide (42), Phantolide (43) and Celestolide /Crysolide (44). 

Substitution reactions. Alkyl 2-alkynylbenzoates are activated by the Au(I) salt toward formation of isocoumarin, thereby weakening the O—C(aik) bond of the esters. Attack of nucleophiles results in the cleavage of the esters.Particularly noteworthy is the formation of tetralins by way of an intramolecular reaction involving an aromatic ring (a C-nucleophile). ... 

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