A fascinating Fe-promoted protocol for the synthesis of N-arylsulfonamides has been developed. Starting from commercially available nitroarenes and sulfonyl chlorides, moderate to excellent yields of the corresponding N-arylsulfonamides can be obtained. In particular, Fe dust was the sole reductant in the transformation and it can be easily performed on a large scale.
Gas-Phase Fragmentations of Anions Derived from <b><i>N</i></b>-Phenyl Benzenesulfonamides
作者:John A. Hibbs、Freneil B. Jariwala、Carl S. Weisbecker、Athula B. Attygalle
DOI:10.1007/s13361-013-0671-4
日期:2013.8.1
addition to the well-known SO2 loss, there are several additional fragmentation pathways that gas-phase anions derivedfrom N-phenyl benzenesulfonamides and its derivatives undergo upon collisional activation. For example, N-phenyl benzenesulfonamide fragments to form an anilide anion (m/z 92) by a mechanism in which a hydrogen atom from the ortho position of the benzenesulfonamide moiety is specifically
除了众所周知的 SO 2损失之外,还有几种额外的碎裂途径,来自N-苯基苯磺酰胺及其衍生物的气相阴离子在碰撞活化时会经历这些碎裂途径。例如,N-苯基苯磺酰胺片段形成苯胺阴离子(m / z 92),其机理是苯磺酰胺部分邻位的氢原子特异性转移到电荷中心。此外,在最初的 SO 2消除后,形成的产物离子主要经历环间 H 2损失以形成咔唑阴离子 ( m / z166)因为竞争的环内H 2损失在能量上明显不太有利。使用氘标记的化合物进行的串联质谱实验的结果证实,环间机制是首选途径。此外,N-苯基苯磺酰胺及其衍生物也发生苯基自由基损失,形成质荷比为155的自由基离子,违反了所谓的“偶电子规则”。 在新窗口中打开图片 数字 ㅟ
A polarizing plate protective film comprising a cellulose ester, and a saccharide ester compound in which all or a part of OH groups in Compound (A) or in Compound (B) are esterified, wherein Compound (A) consists of one of a furanose structure and a pyranose structure, and Compound (B) consists of two to twelve of at least one type of a furanose structure and a pyranose structure which are bonded in Compound (B); wherein the polarizing plate protective film exhibits Ro of 0-10 nm and Rt of −30 to +20 nm.
A cellulose compound film containing a cellulose compound having two or more substituents whose polarizability anisotropies Δα calculated by mathematical formula (1) are different from each other, wherein substitution degrees of the following substituents A and B in the cellulose compound satisfy relationship as defined by mathematical formula (A1), in which the substituent A has the lowest Δα and the substituent B has the highest Δα:
Δ
α
=
α
x
-
α
y
+
α
z
2
Mathematical
formula
(
1
)
wherein, in characteristic values obtained after diagonalization of polarizability tensor, αx is the largest component, αy is the second largest component, and αz is the smallest component;
DS
B
2+
DS
B
3−
DS
B
6≧−0.1 Mathematical formula (A1)
wherein DS
B
2, DS
B
3, and DS
B
6 represent a substitution degree of the substituent B at the 2-, 3-, or 6-position of a β-glucose ring constituting unit of cellulose, respectively; and
an optical compensation film, a polarizing plate, and a liquid crystal display device, using the cellulose compound film.
elusive Pd-catalyzed enantioselective intramolecular allenylic substitution rather than intermolecular allenylic substitution is the enantio-determining step in this cycloaddition. By tuning the ligands, a Pd-catalyzed enantioselective desymmetric allenylic substitution leading to linear axially chiral tri-substituted allenes or a Pd-catalyzed tandem desymmetric allenylic substitution/β-vinylic hydrogen