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Nitrile oxides, cycloaddition with from primary nitro compounds

Aliphatic nitro compounds are versatile building blocks and intermediates in organic synthesis,14 15 cf. the overview given in the Organic Syntheses preparation of nitroacetaldehyde diethyl acetal.16 For example, Henry and Michael additions, respectively, lead to 1,2- and 1,4-difunctionalized derivatives.14 18 1,3-Difunctional compounds, such as amino alcohols or aldols are accessible from primary nitroalkanes by dehydration/1,3-dipolar nitrile oxide cycloaddition with olefins (Mukaiyama reaction),19 followed by ring cleavage of intermediate isoxazolines by reduction or reduction/hydrolysis.20 21... [Pg.243]

Nitrile oxide J -I- 2 cycloaddition.1 A key step in a recent stereospecific synthesis of biotin (6) from cycloheptene (1) is an intramolecular [3 + 2]cyclo-addition of a nitrile oxide (a), obtained by dehydration of a primary nitro compound (3), preferably with phenyl isocyanate. This cycloaddilion is more efficient than the well-known olefinic nitrone cycloaddition. The carbon atoms in 6 derived from cycloheptene are marked with asterisks. [Pg.309]

As discussed in Section 6.2, nitro compounds are good precursors of nitrile oxides, which are important dipoles in cycloadditions. The 1,3-dipolar cycloaddition of nitrile oxides with alkenes or alkynes provides a straightforward access to 2-isoxazolines or isoxazoles, respectively. A number of ring-cleaving procedures are applicable, such that various types of compounds may be obtained from the primary adducts (Scheme 8.18). There are many reports on synthetic applications of this reaction. The methods for generation of nitrile oxides and their reactions are discussed in Section 6.2. Recent synthetic applications and asymmetric synthesis using 1,3-dipolar cycloaddition of nitrile oxides are summarized in this section. [Pg.258]


See other pages where Nitrile oxides, cycloaddition with from primary nitro compounds is mentioned: [Pg.6]    [Pg.167]    [Pg.430]    [Pg.439]   
See also in sourсe #XX -- [ Pg.273 ]




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4-Nitro- -nitril

Cycloaddition compounds

Cycloaddition oxide

Cycloaddition with

Cycloaddition with nitrile oxides

Cycloadditions oxidative

From nitrile oxides

From nitriles

From nitro compounds

Nitrile compounds

Nitrile oxide cycloaddition

Nitrile oxides

Nitrile oxides cycloadditions

Nitriles cycloaddition

Nitriles cycloadditions

Nitriles from nitrile oxides

Nitriles from nitro compounds

Nitriles nitrile oxides

Nitriles nitro

Nitro 4-oxid

Nitro compounds oxidation

Nitro cycloadditions with

Oxidative cycloaddition

Oxidative cycloaddition with

Oxidative nitriles

Primary nitro compounds

Primary nitro compounds oxidation

Primary oxidation

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