Synthesis and configurations of O-substituted hydroximoyl chlorides. Stereochemistry and mechanism of alkoxide ion substitution at the carbon-nitrogen double bond

1985 ◽  
Vol 50 (7) ◽  
pp. 993-997 ◽  
Author(s):  
James Elver Johnson ◽  
Abdolkarim Ghafouripour ◽  
Yvonne Kunz Haug ◽  
A. Wallace Cordes ◽  
William T. Pennington ◽  
...  
Keyword(s):  
Double Bond ◽  
Ion Substitution ◽  
Nitrogen Double Bond

Mechanism of amine and amide ion substitution reactions at the carbon-nitrogen double bond

1985 ◽  
Vol 50 (18) ◽  
pp. 3348-3355 ◽  
Author(s):  
James Elver Johnson ◽  
Abdolkarim Ghafouripour ◽  
Mohammad Arfan ◽  
Susan L. Todd ◽  
Deborah A. Sitz
Keyword(s):  
Double Bond ◽  
Substitution Reactions ◽  
Ion Substitution ◽  
Nitrogen Double Bond

Nucleophilic Attack on the Carbon - Nitrogen Double Bond Leading to Tetrahedral Intermediates with Conformationally Restricted Stereochemistry

2008 ◽  
Vol 61 (11) ◽  
pp. 888 ◽  
Author(s):  
James E. Johnson ◽  
Lei Lu ◽  
Yi Li ◽  
Mei Hou ◽  
Jeffrey E. Rowe
Keyword(s):  
Double Bond ◽  
Chloride Ion ◽  
Chair Conformation ◽  
Nucleophilic Attack ◽  
Boat Conformation ◽  
Conformationally Restricted ◽  
Ion Substitution ◽  
Rate Ratios ◽  
Nitrogen Double Bond ◽  
Tetrahedral Intermediates

Methoxide ion substitution on 4-chloro-1H-2,3-benzoxazine 4 has been investigated. The rates of cyclization have been measured for (Z)- and (E)-O-(2-hydroxyethyl)benzohydroximoyl halides (PhC(X)=NOCH2CH2OH; X = Cl or Br) using potassium t-butoxide to generate alkoxide ions from the alcohols. The element effect for the Z and E isomers are kZBr/kZCl = 3.08 and kEBr/kECl = 2.38. The Z-to-E rate ratios are 0.25 (chlorides) and 0.33 (bromides). These reactions are proceeding by rate-determining nucleophilic attack by the alkoxide ion on the carbon–nitrogen double bond (AN# + DN). The restricted stereochemistry of the tetrahedral intermediates suggests that the E-hydroximoyl bromide and chloride may be undergoing unassisted ionization to form a zwitterionic intermediate that leads to product. Alternatively, the chair conformation of the tetrahedral intermediate may be undergoing a ring flip to a boat conformation in which there are antiperiplanar electron pairs that assist in the ionization of the bromide or chloride ion.

ChemInform Abstract: MECHANISM OF AMINE AND AMIDE ION SUBSTITUTION REACTIONS AT THE CARBON-NITROGEN DOUBLE BOND

1985 ◽  
Vol 16 (52) ◽  
Author(s):  
J. E. JOHNSON ◽  
A. GHAFOURIPOUR ◽  
M. ARFAN ◽  
S. L. TODD ◽  
D. A. SITZ
Keyword(s):  
Double Bond ◽  
Substitution Reactions ◽  
Ion Substitution ◽  
Nitrogen Double Bond

Additions and Corrections - Mechanism of Amine and Amide Ion Substitution Reactions at the Carbon-Nitrogen Double Bond

1986 ◽  
Vol 51 (11) ◽  
pp. 2156-2156
Author(s):  
James Johnson ◽  
Abdolkarim Ghafouripour ◽  
Mohammad Arfan ◽  
Susan Todd ◽  
Deborah Sitz
Keyword(s):  
Double Bond ◽  
Substitution Reactions ◽  
Ion Substitution ◽  
Nitrogen Double Bond

Configuration stability at the carbon-nitrogen double bond

1962 ◽  
Vol 3 (26) ◽  
pp. 1269-1274 ◽  
Author(s):  
D.Y. Curtin ◽  
C.G. McCarty
Keyword(s):  
Double Bond ◽  
Nitrogen Double Bond

Mechanisms of Nucleophilic Attack at Carbon Nitrogen Double-Bonds: The Reaction of Benzohydrazonoyl Halides With Amines

1987 ◽  
Vol 40 (10) ◽  
pp. 1777 ◽  
Author(s):  
AF Hegarty ◽  
P Rigopoulos ◽  
JE Rowe
Keyword(s):  
Double Bond ◽  
Nucleophilic Attack ◽  
Rate Data ◽  
Double Bonds ◽  
Nitrogen Double Bond

Rate data for the reaction of a series of benzohydrazonoyl halides with pyrrolidine and butan- 1-amine at 303 K are presented. Linear Hammett plots were obtained with each amine. The mechanism of the reactions and the stereochemical outcome of these displacements at the carbon-nitrogen double bond are discussed.

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