Characterization of Alkylphenols by Acetylation and Proton Magnetic Resonance.

Amberlyst-15-catalyzed alkylation of phenolics with branched alkenes. Rearrangement of tert-alkylphenols and catechols to sec-alkyl isomers

“…The isomers were identified by GC/MS as 3-(3-hexyl)catechol, 3-(2-hexyl)catechol, 4-(3-hexyl)catechol, and 4-(2-hexyl)catechol, respectively: mass spectrum, m/z (% rel intensity) 194 ( 15) P+, 165 (3) (P -C2H5)+, 151 (20) (P -C3H7)+, 123 (100) C6H3(OH)2CH2+; 194 (19) P+, 137 (100) C6H3(OH)2C+H(CH3); 194 (19) P+, 165 (16) (P -C2H5)+, 151 (45) (P -C3H7)+, 123 (100) C6H3(OH) 2CH2+;194 (16) P+, 137 (100) C6H3(OH)2C+H(CH3). The NMR spectrum of the product was consistent with the literature, and the methine region of the spectrum is shown in Figure 2 (Lindeman and Nicksic, 1964).…”

“…This observation is contrary to the report that ortho substitution can be controlled by use of a more active catalyst and more severe reaction conditions since ortho derivatives can undergo isomerization to their para form (Rosenwald, 1978). Further examination of the 150 °C product by NMR shows the ortho isomers to be mostly sec-dodecylphenols ( 3.0, PhCH) (30%) and the para isomers to be sec-dodecylphenols ( 2.5, PhCH) (18%) and ferf-dodecylphenols (mostly para, 52%) (Lindeman and Nicksic, 1964;Crutchfield et al, 1964). This analysis indicated to us that a significant rearrangement reaction was occurring at the higher temperature, but the product mixture was too complex for a detailed study.…”

Acid-catalyzed reactions of 2,2,2-trifluorodiazoethane for analysis of functional groups by fluorine-19 nuclear magnetic resonance spectrometry

“…All derivative l9F NMR peaks observed were triplets as CF3CHN2 + ROH -CF3CHzOR + Nzt (4) would be expected ( Figure 1). Table I lists several alcohols employed in this study and corresponding I9F chemical shifts and product yield as determined by NMR integration.…”

“…Since the geometry and dimensions of the spray chamber, as well as devices such as mixer paddles and impact beads all influence the transport process significantly (2), the following discussion more appropriately describes t, as the tramport efficiency. A number of studies have been published in which values oft, were determined either for fundamental purposes (3)(4)(5)(6)(7)(8)(9) or for the comparison of various nebulizer/spray chamber systems (10-12).…”

Characterization of phenols from coal liquefaction products by tin-119 nuclear magnetic resonance spectrometry

“…NMR spectrometry methods have been used for estimation of hydroxyl groups present in coal extracts (11). The NMR analyses of acetylated phenols (12) and trimethylsilyl derivatives of model phenols (13) have also been used for isomer analysis of phenols and characterization of hydroxyl groups in coal liquefaction oils. The 19F NMR analyses of hexafluoroacetone adducts (14-16) or trifluoroacetyl derivatives (17)(18)(19)(20) and ^Si NMR (21) have been described for the hydroxyl content analysis in synthetic fuels and isomer analysis of phenols.…”