A new preparation of substituted 4<i>H</i>-1-benzothiopyran-4-ones from c(α)<i>N</i>-benzoylhydrazones or c(α)<i>N</i>-carboalkoxyhydrazones and methyl thiosalicylate
作者:Kristen L. French、April J. Angel、Angela R. Williams、Douglas R. Hurst、Charles F. Beam
DOI:10.1002/jhet.5570350109
日期:1998.1
C(α)N-Benzoylhydrazones or C(α),N-carboalkoxyhydrazones were dilithiated with excess lithium diisopropylamide, and the dianion-type intermediates were condensed with lithiated methylthiosalicylate, followed by cyclization/hydrolysis to substituted4H-1-benzothiopyran-4-ones (thioflavones/thiochromones).
用过量的二异丙基氨基锂将C(α)N-苯甲酰肼或C(α)N-羰基烷氧基hydr酮二锂化,将二价阴离子型中间体与锂化的硫代水杨酸甲酯缩合,然后环化/水解成取代的4 H -1-苯并噻吩并- 4-one(硫代黄酮/硫代色酮)。
Water soluble chiral diphoshpines
申请人:——
公开号:US20040102649A1
公开(公告)日:2004-05-27
The invention concerns a water soluble compound of formula (a) wherein: A represents naphthyl or phenyl; and Ar
1
and Ar
2
independently represent a saturated or aromatic carbocyclic group; X
a
, X
b
are independently selected among an amino group, an ammonium group and an amino group modified by a linear polyoxyalkylene chain, provided that at least one of X
a
and X
b
represents ammonium or modified amino.
Compounds of formula VII are described:
1
wherein A represents phenyl or naphthyl and
Ar
1
and Ar
2
independently represent a saturated or aromatic carbocyclic group. The compounds may be prepared by reducing the nitrile functions of a compound of formula I:
2
描述了式 VII 的化合物:
1
其中 A 代表苯基或萘基,且
Ar
1
和 Ar
2
分别代表饱和或芳香碳环基团。这些化合物可通过还原式 I 化合物的腈基官能团来制备:
2
Stereoselective Synthesis of Both <i>syn- </i>and <i>anti</i>-<i>N</i>-<i>tert</i>-Alkylamines Using Highly Stereospecific Crotylation of Ketone-Derived Acylhydrazones with Crotyltrichlorosilanes
作者:Chikako Ogawa、Masaharu Sugiura、Shū Kobayashi
DOI:10.1021/jo0258599
日期:2002.7.1
Crotyltrichlorosilanes reacted with ketone-derived N-benzoylhydrazones in DMF without any catalyst. This is the first example of highly stereospecific crotylation of ketimine analogues leading to both syn- and anti-N'-tert-alkyl-N-benzoylhydrazines. Different reactivities between (Z)- and (E)-crotylsilanes in terms of yields and selectivities were observed. A kinetic study with both geometrically pure (Z)- and (E)-crotylsilanes was performed. These reactions are most likely to proceed via a cyclic chairlike transition state where the aromatic group of hydrazones takes an axial position. Both diastereomers of allylation products can be converted to the corresponding alpha,alpha-disubstituted homoallylic amines without epimerization.
Burk Mark J., Martinez Jose P., Feaster John E., Cosford Nick, Tetrahedron, 50 (1994) N 15, S 4399-4428
作者:Burk Mark J., Martinez Jose P., Feaster John E., Cosford Nick