536-78-7Relevant articles and documents
Interconversion of nicotine enantiomers during heating and implications for smoke from combustible cigarettes, heated tobacco products, and electronic cigarettes
Moldoveanu, Serban C.
, p. 667 - 677 (2022/02/02)
Physiological properties of (R)-nicotine have differences compared with (S)-nicotine, and the subject of (S)- and (R)-nicotine ratio in smoking or vaping related items is of considerable interest. A Liquid Chromatography-Mass Spectrometry/Mass Spectrometry (LC-MS/MS) method for the analysis of (S)- and (R)-nicotine has been developed and applied to samples of nicotine from different sources, nicotine pyrolyzates, several types of tobacco, smoke from combustible cigarettes, smoke from heated tobacco products, e-liquids, and particulate matter obtained from e-cigarettes aerosol. The separation was achieved on a Chiracel OJ-3 column, 250 × 4.6 mm with 3-μm particles using a nonaqueous mobile phase. The detection was performed using atmospheric pressure chemical ionization (APCI) in positive mode. The only transition measured for the analysis of nicotine was 163.1 → 84.0. The method has been summarily validated. For the analysis, the samples of tobacco and smoke from combustible cigarettes were subject to a cleanup procedure using solid phase extraction (SPE). It was demonstrated that nicotine upon heating above 450°C for several minutes starts decomposing, and some formation of (R)-enantiomer from a sample of 99% (S)-nicotine is observed. An analogous process takes place when a 99% (R)-nicotine is heated and forms low levels of (S)-nicotine. This interconversion has the effect of slightly increasing the content of (R)-nicotine in smoke compared with the level in tobacco for combustible cigarettes and for heated tobacco products. The (S)/(R) ratio of nicotine enantiomers in e-liquids was identical with the ratio for the particulate phase of aerosols generated by e-cigarette vaping.
A 2 - chloro - 5 - ethyl pyridine preparation method (by machine translation)
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Paragraph 0019; 0037; 0038, (2017/08/25)
The invention discloses a method for synthesizing 2 - chloro - 5 - ethyl pyridine method, by Suzuki reaction with 2 - chloro - 5 - bromo pyridine or by Wittig reaction with 2 - chloro - 5 - formyl pyridine is converted into 2 - chloro - 5 - vinyl pyridine; further uses the type (I) selective hydrogenation catalyst-containing structure, wherein R is cyclohexyl, butyl or phenyl, L is pyridine or unsaturated including nitrogen Cabeen, the 2 - chloro - 5 - vinyl pyridine is converted into 2 - chloro - 5 - ethyl pyridine. The method of the invention has a high selectivity, high yield and the advantage of convenient purification. (by machine translation)
Methyl Hydrazinocarboxylate as a Practical Alternative to Hydrazine in the Wolff-Kishner Reaction
Cranwell, Philippa B.,Russell, Andrew T.,Smith, Christopher D.
, p. 131 - 135 (2015/12/26)
Herein we describe a facile protocol for the reduction of aromatic ketones and aldehydes to the corresponding methylene unit. The procedure involves isolation of a carbomethoxyhydrazone intermediate that is easily decomposed to the reduced product without the requirement for large quantities of pernicious hydrazine.