An efficient [3 + 2] cycloaddition reaction of difluoromethyl or trifluoromethyl hydrazonoyl bromides with trifluoromethyl-substituted alkenes was investigated to produce a variety of 3,5-bis(fluoroalkyl)pyrazoles/pyrazolines in moderate to good yields. This protocol features obvious advantages such as easily available and stable substrates, step economy, gram-scalability and simple operation, providing a novel and practical method for the preparation of 3,5-bis(fluoroalkyl)pyrazoles/pyrazolines.
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Synthesis of 3,5-bis(fluoroalkyl)pyrazoles/pyrazolines [3 + 2] cycloaddition of di/trifluoroacetohydrazonoyl bromides and trifluoromethyl-substituted alkenes.
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An efficient [3 + 2] cycloaddition reaction of difluoromethyl or trifluoromethyl hydrazonoyl bromides with trifluoromethyl-substituted alkenes was investigated to produce a variety of 3,5-bis(fluoroalkyl)pyrazoles/pyrazolines in moderate to good yields. This protocol features obvious advantages such as easily available and stable substrates, step economy, gram-scalability and simple operation, providing a novel and practical method for the preparation of 3,5-bis(fluoroalkyl)pyrazoles/pyrazolines.
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