Convenient asymmetric synthesis of both enantiomers of 3,4-disubstituted 3,4-dihydro-1,4-benzoxazin-2-ones
作者:Eunjee Youk、Wongi Park、Yong Sun Park
DOI:10.1080/00397911.2018.1444769
日期:2018.6.3
ABSTRACT Bothenantiomers of N-substituted 3-arylated 3,4-dihydro-1,4-benzoxazin-2-ones were conveniently synthesized up to 93:7 er based on the dynamic kinetic resolution of either (R)-pantolactone- or l-mandelate-derived α-bromo arylacetates in nucleophilic substitution with N-alkylated 2-aminophenols. GRAPHICAL ABSTRACT
摘要 基于 (R)-泛内酯-或 l 的动态动力学分辨率,N-取代的 3-芳基化 3,4-二氢-1,4-苯并恶嗪-2-酮的两种对映异构体均可方便地合成至 93:7 er。 -扁桃酸衍生的α-溴芳基乙酸酯与N-烷基化2-氨基苯酚亲核取代。图形概要
Antioxidant and bisaminophenol derivative
申请人:Shiraki Yasushi
公开号:US20060208227A1
公开(公告)日:2006-09-21
The present invention provides antioxidants made of an aromatic hydroxyamine derivative having a structure represented by the general formula (I):
wherein R
1
, R
2
and R
3
are each independently a hydrogen atom or an alkyl group having 1 to 20 carbon atoms; X is a hydrogen atom or an OH group; Y is a hydrogen atom or an NHR
1
group; A is a direct bond, —O—, —NH—, —SO
2
—, —CH
2
— or —C(CH
3
)
2
—, and when an OH group and an NHR
1
group are introduced to a unilateral benzene ring, these groups are respectively bonded to adjacent positions of the benzene ring; and n is 0 or 1 with the proviso that when n is 0, R
1
is not a hydrogen atom, as well as bisaminophenol derivatives represented by the above general formula (I) wherein n is 1; R
2
and R
3
are each a hydrogen atom; X is an OH group; Y is an NHR
1
group; A is —C(CH
3
)
2
—; and R
1
is isopropyl, isobutyl or isohexyl. The aromatic hydroxyamine derivatives having a structure represented by the general formula (I), in particular, the bisaminophenol derivatives as novel substances, exhibit an excellent oxidation-inhibiting property, and are usable as antioxidants or polymerization inhibitors.
The present invention provides antioxidants made of an aromatic hydroxyamine derivative having a structure represented by the general formula (I):
wherein R
1
, R
2
and R
3
are each independently a hydrogen atom or an alkyl group having 1 to 20 carbon atoms; X is a hydrogen atom or an OH group; Y is a hydrogen atom or an NHR
1
group; A is a direct bond, —O—, —NH—, —SO
2
—, —CH
2
— or —C(CH
3
)
2
—, and when an OH group and an NHR
1
group are introduced to a unilateral benzene ring, these groups are respectively bonded to adjacent positions of the benzene ring; and n is 0 or 1 with the proviso that when n is 0, R
1
is not a hydrogen atom, as well as bisaminophenol derivatives represented by the above general formula (I) wherein n is 1; R
2
and R
3
are each a hydrogen atom; X is an OH group; Y is an NHR
1
group; A is —C(CH
3
)
2
—; and R
1
is isopropyl, isobutyl or isohexyl. The aromatic hydroxyamine derivatives having a structure represented by the general formula (I), in particular, the bisaminophenol derivatives as novel substances, exhibit an excellent oxidation-inhibiting property, and are usable as antioxidants or polymerization inhibitors.
N-Substituted Carbamic Acid Ester Production Method, Isocyanate Production Method Using Such N-Substituted Carbamic Acid Ester, And Composition For Transfer And Storage Of N-Substituted Carbamic Acid Ester Comprising N-Substituted Carbamic Acid Ester and Aromatic Hydroxy Compound
申请人:Shinohata Masaaki
公开号:US20110133121A1
公开(公告)日:2011-06-09
The present invention is a method for producing an N-substituted carbamic acid ester derived from an organic amine from an organic amine, a carbonic acid derivative and a hydroxy composition containing one or more types of hydroxy compounds, wherein the organic amine, the carbonic acid derivative and the hydroxy composition are reacted using a urethane production reaction vessel provided with a condenser, a gas containing the hydroxy composition, the compound having the carbonyl group derived from the carbonic acid derivative, and an ammonia formed as a by-product in the reaction, is introduced into the condenser provided in the urethane production reaction vessel, and the hydroxy composition and the compound having the carbonyl group derived from the carbonic acid derivative are condensed, and wherein a stoichiometric ratio of a hydroxy compound contained in the condensed hydroxy composition to the condensed compound having the carbonyl group derived from the carbonic acid derivative is 1 or more, and a ratio of number of carbonyl groups (—C(═O)—) contained in the compound having the carbonyl group derived from the carbonic acid derivative and number of ammonia molecules contained in the ammonia recovered as a gas from the condenser is 1 or less.
N-Substituted Carbamic Acid Ester Production Method, Isocyanate Production Method Using Such N-Substituted Carbamic Acid Ester, and Composition for Transfer and Storage of N-Substituted Carbamic Acid Ester Comprising N-Substituted Carbamic Acid Ester and Aromatic Hydroxy Compound
申请人:Asahi Kasei Chemicals Corporation
公开号:US20140194650A1
公开(公告)日:2014-07-10
The present invention is a method for producing an N-substituted carbamic acid ester derived from an organic amine from an organic amine, a carbonic acid derivative and a hydroxy composition containing one or more types of hydroxy compounds, wherein the organic amine, the carbonic acid derivative and the hydroxy composition are reacted using a urethane production reaction vessel provided with a condenser, a gas containing the hydroxy composition, the compound having the carbonyl group derived from the carbonic acid derivative, and an ammonia formed as a by-product in the reaction, is introduced into the condenser provided in the urethane production reaction vessel, and the hydroxy composition and the compound having the carbonyl group derived from the carbonic acid derivative are condensed, and wherein a stoichiometric ratio of a hydroxy compound contained in the condensed hydroxy composition to the condensed compound having the carbonyl group derived from the carbonic acid derivative is 1 or more, and a ratio of number of carbonyl groups (—C(═O)—) contained in the compound having the carbonyl group derived from the carbonic acid derivative and number of ammonia molecules contained in the ammonia recovered as a gas from the condenser is 1 or less.