Diisopropyl azodicarboxylate DIAD

The mechanistic pathway" " can be divided into three steps 1. formation of the activating agent from triphenylphosphine and diethyl azodicarboxylate (DEAD) or diisopropyl azodicarboxylate (DIAD) 2. activation of the substrate alcohol 1 3. a bimolecular nucleophilic substitution (Sn2) at the activated carbon center. 

Pavan Kumar et al. <2006NJC717> investigated the reaction of diethyl azodicarboxylate (DEAD) or diisopropyl azodicarboxylate (DIAD) with cyclic phosphates or phosphoramides in order to determine the structural preferences in spirocyclic penta- and hexacoordinate aminophosphoranes. They found that sulfur would coordinate to phosphorus to form the [3.3.0] bicyclic compounds 94-96. 

The 3-methyl- and 3-phenyl-l,2,3-oxadiazolinium salts 96 and 97 are capable of oxidizing thiols to disulfides <1995MI817>. New dihydro-1,2,3-benzoxadiazoles, prepared by the reaction of 1,2-benzoquinones with diethyl azodicarboxylate (DEAD) or diisopropyl azodicarboxylate (DIAD) in the presence of triphenylphosphine (Section 5.03.9.4), have been shown to undergo catalytic hydrogenolysis to give phenols (Equation 12) <20050L5139>. 

The hydroxymethyl and carboxyl group of Ser can participate in pyrazole-ring formation, as shown in the transformation of A -protected L-Ser with the Mitsunobu reagent into a /3-lactone which afforded the N-protected serine hydrazide upon treatment with methyl hydrazine. Cyclization to 25 was achieved by diisopropyl azodicarboxylate (DIAD) and TPP [90H(31)79]. 

The C-2 hydroxyl derivative with the unnatural configuration (2-Epi-Sl or 62) was synthesized using Mitsunobu conditions of triphenylphosphine (PPI13), diisopropyl azodicarboxylate (DIAD), and 4-nitrobenzoic acid as the nucleophile, which was subsequently hydrolyzed with K2C03 in MeOH to afford 62 in 64% yield over two steps [34]. Compounds 57 and 2-epi-Sl have been exploited as common intermediates in diversification of the C-2 position. Hydroxyl 57 has been utilized... 

This reaction was initially reported by Fukuyama and co-workers in 1995. It is a two-step conversion of primary amines into secondary amines via ortho-nitrobenzenesulfonation in conjunction with the Mitsunobu Reaction and subsequent removal of the o-nitrobenzenesulfonyl group by thiophenol. Therefore, this reaction is generally known as the Fukuyama amine synthesis. In addition, it is also referred to as the Fukuyama-Mitsunobu A -alkylation," Fukuyama-Mitsunobu alkylation, Fukuyama-Mitsunobu condition, Fukuyama-Mitsunobu procedure, or Fukuyama-Mitsunobu Reaction. In this reaction, the o-nitrobenzenesulfonyl-protected amine is alkylated with alcohol in the presence of PPhs and diethyl azodicarboxylate (DEAD) or diisopropyl azodicarboxylate (DIAD), and the deprotection occurs in a very mild condition (almost neutral ). The o-nitrobenzenesulfonyl group is simply called the Fukuyama sulfonamide protecting groupThis reaction has become a versatile method... 

This reaction was first reported by Mitsunobu in 1967. It is the alkylation of compounds with active protons by using primary or secondary alcohols as the alkylating agents in combination with triphenylphosphine and diethyl azodicarboxylate (DEAD) or diisopropyl azodicarboxylate (DIAD), to form molecules like esters, ethers, thioethers, and amines. Therefore, this reaction is generally known as the Mitsunobu reaction or Mitsunobu coupling. In addition, the specific reaction for forming esters by means of DEAD (or DIAD) and PPhs is generally referred to as the Mitsunobu esterification." Occasionally, the Mitsunobu reaction is also called the Mitsunobu transformation (for the conversion of alcohol into amines) or Mitsunobu cyclizafion (for the formation of cyclic compounds). Because of its intrinsic features of stereospecificity, as well as its occurrence in neutral media and at room temperature without a prerequisite activation of alcohol, this reaction has been extensively studied and used to synthesize a variety of compounds since 1970. 

Preparative Methods compound (1) can be prepared in two steps as shown in eq 1 first aziridination of c/s-but-2-ene-l,4-diol (1 equiv) is done with TsNClNa (1.1 equiv) and PhMe3NBr3 (0.1 equiv) in acetonitrile at 25 °C for 3 days. This is foUowedby treatment of the diol with diisopropyl azodicarboxylate (DIAD, 1.5 equiv) and PPhs (1.5 equiv) in THE at —78°C for 1 h followed by stirring at 25 °C for 7 days. ... 

A very mild method for the preparation of isocyanates from primary amines (RNH2) and carbon dioxide (CO2) involves the use of a Mitsunobu zwitterion generated from either diisopropyl azodicarboxylate (DIAD) or di-tert-butyl azodicarboxylate and triphenylphosphine or tri-n.-butylphosphine. 

General procedure for the synthesis of aliphatic isocyanates [196] At —10 to —5 °C, anaerobic grade CO2 was gently bubbled through a solution of the freshly distilled amine in dichloromethane. More CO2 was then vigorously bubbled through the solution for 30-60 min. In a separate flask, a stirred, cold (—20 °C) solution of PPhs in dichloromethane was treated with diisopropyl azodicarboxylate (DIAD) or... 

The explosive hydrogen azide can be replaced by less dangerous diphenylphosphoryl azide (DPPA). In the presence of this reagent, triphenylphosphane and diisopropyl azodicarboxylate (DIAD) the anti homoaUylic alcohol 151 is converted into the syn azide... 

K3[Fe(CN)6] was applied as a secondary oxidant in a chemoselective osmium(VI)-catalyzed oxidation of benzylic, aUylic, and propargylic alcohols. An uncommon oxidation agent, diisopropyl azodicarboxylate (DIAD), can be used as an effective terminal oxidant ° in this case 1,2-diols were oxidized to hydroxyl ketones or diketones depending on the amount of DIAD used. Diaziridinone (Scheme 13) as oxidant allows the reactions to... 

The Mitsunobu Reaction. A mixture of triphenylphosphine (TPP) and diethyl azodicarboxylate (DEAD) is generally used however, diisopropyl azodicarboxylate (DIAD) is cheaper and works just as well. The overall reaction enables the replacement of the hydroxyl group of an alcohol by a nucleophile X (eq 1). 

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