Table 1 Optimization of reaction conditionsa

From: A mild and practical approach to N-CF3 secondary amines via oxidative fluorination of isocyanides

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Entry

Oxidant

[F−] source

[HF] source

Solvent

Yield (%)b

1

DIH

Et3N·HF

Et3N·3HF

MTBE

N.D.

2

NIS

Et3N·HF

Et3N·3HF

MTBE

N.D.

3

NBS

Et3N·HF

Et3N·3HF

MTBE

N.D.

4

DBDMH

Et3N·HF

Et3N·3HF

MTBE

N.D.

5

I2

Et3N·HF

Et3N·3HF

MTBE

5

6

I2

Py·HF

Py·9HF

MTBE

N.D.

7

I2

AgF

Et3N·3HF

MTBE

16

8

I2

AgF

Py·9HF

MTBE

N.D.

9

I2

AgF

HSiEt3

MTBE

N.D.

10

I2

AgF

HSi(OEt)3

MTBE

N.D.

11

I2

AgF

HSitBuMe2

MTBE

48

12

I2

AgF

HSitBuMe2

MeCN

N.D.

13

I2

AgF

HSitBuMe2

DCM

N.D.

14

I2

AgF

HSitBuMe2

1,4-dioxane

97c

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  1. MTBE methyl tert-butyl ether, N.D. no detected.
  2. aGeneral reaction conditions: 1a (0.5 mmol, 1.0 equiv), oxidant (0.55 mmol, 1.1 equiv), [F−] source (AgF added as 7.0 equiv; Et3N·3HF and Py·9HF added as 12.0 equiv, simultaneously serving as [HF] sources), [HF] source (HSiEt3, HSi(EtO)3, and HSitBuMe2 added as 1.4 equiv), solvent (3.0 mL), 40 °C, 4 h.
  3. bYields are determined by 19F NMR analysis using PhCF3 as the internal standard.
  4. cIsolated yield.
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