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51.
Nucleophilic substitution reactions of (CH3NPF3)2 with alcohols have been studied. In case of (CH3NPF3)2 as starting material an excess of this compound acts as an HF-acceptor. In this way mono- or di-alkoxysubstituted diazadiphosphetidines are obtained. If the starting material is a substituted ring or if an aromatic alcohol is employed, the alcohol component has to be in form of the lithium salt.
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52.
Summary The result of the chlorination of (CH3CH2NPF3)2 and (CH3CH2CH2NPF3)2 with chlorine under UV-radiation were the new compounds CH3CH2(NPF3)2CH2CH2Cl and CH3CH2CH2(NPF3)2CH2CH2CH2Cl. The reaction of CH3(NPF3)2CH2Cl with KCN and crown-ether gave the new compound CH3(NPF3)2CH2CN.
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53.
Summary Using 1-chloromethyl-2,2,2,4,4,4-hexafluoro-3-methyl-1,3,25,45-diazadiphosphetidine as starting material for nucleophilic reactions, the following new compounds were prepared: 2,2,2,4,4-pentafluoro-4-methoxy-1-propyl-3-methyl-1,3,25,45-diazadiphosphetidine, 1-benzyl-2,2,2,4,4-pentafluoro-4-methoxy-3-methyl-1,3,25,45-diazadiphosphetidine, and 1-benzyl-2,2,2,4,4-pentafluoro-4-methylamino-3-methyl-1,3,25,45-diazadiphosphetidine
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54.
The reaction of (CH3NPF3)2 with NH3 and primary aliphatic and aromatic amines in the molar ratio 3:2 yields (CH4NPF4)2 and the monoamino substituted fluordiaza-diphosphetidines. These react with N-Trimethylsilyl-methylamine to the mixed diamino substituted compounds.With 1,4-Diazabicyclo[2.2.2]octan as HF-acceptor a second step of nucleophilic substitution with NH3 and primary amines is possible. In the case of ammonia a by- product has been identified as the 1:1 adduct of (CH3NPF2NH2)2 with 1,4-diazabicyclo[2.2.2]octan.
Herrn Prof. Dr.O. Hromatka zum 80. Geburtstag gewidmet.  相似文献   
55.
The title compounds ( 3 , 8 , 9 and 10 ) were efficiently synthesized, and their substitution reactions with various nucleophiles were carried out. The effects of leaving group, sulfur‐substituent, solvent, reaction temperature, and the nature of the nucleophiles on the reactivity and SN2/SN2′ regioselectivity were studied and rationalized with semi‐empirical calculations.  相似文献   
56.
Abstract

Metal complexes of 1-phosphino-2-sulfenylferrocene (fesulphos ligands) act as highly efficient catalysts in Pd-catalyzed desymmetrization of meso heterobicyclic alkenes and in Cu-catalyzed formal aza Diels–Alder reaction of Danishefsky diene to N-sulfonyl imines.  相似文献   
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The 2,2′:6′,2″-terpyridines 7a-c were prepared in good yield by reacting α-acetoxy-α-chloro-β-keto-esters 3a-c with bis-amidrazone 4 and 2,5-norbornadiene 6 in ethanol at reflux. Compounds 3a and 3b gave the 2,2′:6′,2″-terpyridines 9a and 9b, respectively, in moderate yield when treated with compound 4 and enamine 8.  相似文献   
60.
A functionalized ionic liquid, 3‐(N,N‐dimethyldodecylammonium) propanesulfonic acid hydrogen sulphate ([DDPA][HSO4]) has been used as catalyst for the aza‐Michael reactions of aromatic amines with α,β‐unsaturated compounds at room temperature to produce β‐amino compounds in good yields. The catalyst can be reused for several times without obvious loss of the catalytic activity.  相似文献   
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