Diels-Alder reactions of nitrosobenzenes

The hetero-Diels-Alder reaction of nitrosobenzene with 2//-pyran-2-one, however, gives an adduct 9 which rapidly loses carbon dioxide and, after addition of another molecule of nitrosobenzene followed by rearrangement, leads to 10 in low yield89. 

A catalytic version of the asymmetric hetero Diels-Alder reaction of nitrosobenzene with the dienol 18 was also achieved to afford the corresponding optically active cycloadduct 19 with 83% ee. The addition of MS 4 Awas cracial to realize reproducible high enantioselectivity (Eq. 11.10) [19]. 

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See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ , ]

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