通过用13 C或氘进行同位素取代,确定了4-羟基香豆素及其阴离子在光谱中主要具有v(C = O)和v(C = O)特征的谱带。在氯仿,二恶烷或二甲基亚砜溶液中,发现4-羟基香豆素的两种谱带,v(C = O)分别在1704-1733 cm -1和〜1567 cm -1处。在结晶的4-羟基香豆素一水合物的光谱中,在1618和1559 cm -1处有两个谱带与v(C = C)相关,但在1655 cm -1处仅观察到一个v(C = O)谱带。无水4-羟基香豆素具有v(C = O)束带在〜1700 cm -1处,肩部在〜1670 cm -1处。在二甲基亚砜溶液中的4-羟基香豆素阴离子光谱中1660 cm -1处的强谱带是由于离域的v(O = C = O)振动引起的,而1555 cm -1处的谱带则具有部分v(C = C)字符,涉及C(3)但不涉及C(2),支持阴离子的完全离域碳结构。除了固态的无水4
The chemistry of [
13
C]methyl phenyl sulfide is exploited to produce new isotopically labeled precursors that allow for the facile assembly of a wide range of labeled molecules from simple and relatively inexpensive starting materials. These compounds are applicable to a variety of research areas such as quantum computing, metabolism and materials science.
4-Hydroxycoumarin/2-hydroxychromone tautomerism: Infrared spectra of 2-<sup>13</sup>c and 3-D labeled 4-hydroxycoumarin and its anion
作者:Andrew O. Obaseki、William R. Porter、William F. Trager
DOI:10.1002/jhet.5570190234
日期:1982.3
with v (C=C) in the spectrum of crystalline 4-hydroxycoumarin monohydrate, but only a single v (C=O) band at ∼ 1655 cm−1 was observed. Anhydrous 4-hydroxycoumarin has v (C=O) bands at ∼ 1700 cm−1 and a shoulder at ∼ 1670 cm−1. The strong band at 1660 cm−1 in the spectrum of 4-hydroxycommarin anion in dimethylsulfoxide solution is due to a delocalized v (O = C = O) vibration, whereas the band at 1555 cm−1
通过用13 C或氘进行同位素取代,确定了4-羟基香豆素及其阴离子在光谱中主要具有v(C = O)和v(C = O)特征的谱带。在氯仿,二恶烷或二甲基亚砜溶液中,发现4-羟基香豆素的两种谱带,v(C = O)分别在1704-1733 cm -1和〜1567 cm -1处。在结晶的4-羟基香豆素一水合物的光谱中,在1618和1559 cm -1处有两个谱带与v(C = C)相关,但在1655 cm -1处仅观察到一个v(C = O)谱带。无水4-羟基香豆素具有v(C = O)束带在〜1700 cm -1处,肩部在〜1670 cm -1处。在二甲基亚砜溶液中的4-羟基香豆素阴离子光谱中1660 cm -1处的强谱带是由于离域的v(O = C = O)振动引起的,而1555 cm -1处的谱带则具有部分v(C = C)字符,涉及C(3)但不涉及C(2),支持阴离子的完全离域碳结构。除了固态的无水4