Structure–Odor Correlations in Homologous Series of Alkanethiols and Attempts To Predict Odor Thresholds by 3D-QSAR Studies
摘要:
Homologous series of alkane-1-thiols, alkane-2-thiols, alkane-3-thiols, 2-methylalkane-1-thiols, 2-methylalkane-3-thiols, 2-methylalkane-2-thiols, and alkane-1,?-dithiols were synthesized to study the influence of structural changes on odor qualities and odor thresholds. In particular, the odor thresholds were strongly influenced by steric effects: In all homologous series a minimum was observed for thiols with five to seven carbon atoms, whereas increasing the chain length led to an exponential increase in the odor threshold. Tertiary alkanethiols revealed clearly lower odor thresholds than found for primary or secondary thiols, whereas neither a second mercapto group in the molecule nor an additional methyl substitution lowered the threshold. To investigate the impact of the SH group, odor thresholds and odor qualities of thiols were compared to those of the corresponding alcohols and (methylthio)alkanes. Replacement of the SH group by an OH group as well as S-methylation of the thiols significantly increased the odor thresholds. By using comparative molecular field analysis, a 3D quantitative structureactivity relationship model was created, which was able to simulate the odor thresholds of alkanethiols in good agreement with the experimental results. NMR and mass spectrometric data for 46 sulfur-containing compounds are additionally supplied.
Presented in this paper is photoinduced hydroxylation of organic halides, providing a mild access to a range of functionalized phenols and aliphatic alcohols. These reactions generally proceed under mild reaction conditions with no need for a photocatalyst or a strong base and show a wide substrate scope as well as excellent functional group tolerance. This work highlights the unique role of NaI that
Nickel-Catalyzed Reductive Allylation of Tertiary Alkyl Halides with Allylic Carbonates
作者:Haifeng Chen、Xiao Jia、Yingying Yu、Qun Qian、Hegui Gong
DOI:10.1002/anie.201705521
日期:2017.10.9
of all C(sp3) quaternarycenters has been successfully achieved under Ni‐catalyzed cross‐electrophile coupling of allylic carbonates with unactivated tertiary alkyl halides. For allylic carbonates bearing C1 or C3 substituents, the reaction affords excellent regioselectivity through the addition of alkyl groups to the unsubstituted allyliccarbonterminus. The allylicalkylationmethod also exhibits
An extension of nickel-catalyzed reductive coupling between tertiary alkyl halides with allylic carbonates
作者:Yingying Yu、Haifeng Chen、Qun Qian、Ken Yao、Hegui Gong
DOI:10.1016/j.tet.2018.07.057
日期:2018.9
The nickel catalyzed reductive coupling of allyliccarbonates with chloro-cyclotryptamine analogs to construct sterically congested all C(sp3) quaternary centers has been achieved with emphasis on the substrate scope. And the using of dienyl methyleneyl carbonates coupling with a variety of tertiary alkylhalides furnished the dienylated products improved the reaction's applicability.
The present invention relates to carbazole compounds of formula (I) and a semiconducting material comprising such carbazole compounds. It also relates to a process for the preparation of such carbazole compounds, as well as to the use thereof as a semiconducting material, in particular as a host matrix for phosphorescent emitters.