Table 1 O-Alkylation of alcohol using carbocationoids 3

From: Carbocationoids, a concept for controlling highly reactive cationic species

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Entry

Carbocationoid 3

Preservation time (h)*

Product

Yield (%)†

1

3a

1

7a

89 (88)

2

3a

20

7a

85

3‡

–

1

7a

not detected

4

3b

1

7b

89, 87§

5

3b

20

7b

89 (87)

6||

–

–

7b

<3

  1. *Preservation time at 0 °C for carbocationoids 3 prior to use. †Calculated by 1H nuclear magnetic resonance (NMR) spectroscopic analysis using an internal standard. Isolated yields are given in parentheses. ‡Reaction was conducted without the use of 4a. §Alkylation was conducted using N-isobutylmorpholine instead of pempidine. ||After treating 5b (2 equiv.) with Tf2O (2 equiv.) and pempidine (2.2 equiv.) at −78 °C for 1 h, 6 (1 equiv.) and pempidine (2.1 equiv.) were added. The reaction mixture was stirred at room temperature for 3 h.
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