Page 606 - Advanced Organic Chemistry Part B - Reactions & Synthesis

580 Scheme 6.17. Rearrangements of Orthoamides and Imidates

CHAPTER 6 1 a
CH 2 Ph (CH 3 ) 2 NC(OCH 3 ) 2 CH 2 Ph
Concerted N N
Cycloadditions, CH 3
CH 2 CH 3
Unimolecular
Rearrangements, and HO CH 2 CH 3 160°C CH 2 CN(CH 3 ) 2 45%
Thermal Eliminations
O
2 b
CH 2 CON(CH 3 ) 2
PhCH 2 O CH 3 (CH 3 ) 2 NC(OCH 3 ) 2
PhCH 2 O CH 3
CH 2 CH 3
CH 2
OH
160°C
92%
3 c
(CH 3 ) 2 NC(OCH 3 ) 2
OCH 3
(CH 3 ) 2 N OCH 3
CH 3
OTBDMS O
120°C OTBDMS
OH
O
4 d
CH 3 CH 3 N(CH 3 ) 2
(CH 3 ) 2 NC(OCH 3 ) 2
CH 3
CH 3 CH 3
HO 110°C 50%
CO 2 CH 3 CO 2 CH 3
5 e H
(CH 3 ) 2 N
(CH 3 ) 2 NC(OCH 3 ) 2 H
O
N CH 3
HO
H
TBDMSO CO 2 CH 3 120°C N
H 93%
TBDMSO CO 2 CH 3
6 f
O O 1) LiHMDS O O
TBDMS-Cl
N N
2) 135°C H CH 3
40 h CH 3
CH 3
7 g CH 3 CH 3 O
CH 3 CH 3
O O
NH 8% PdCl 2 O O NHCCCl 3
O CCl 3
OCH 2 Ph
OCH 2 Ph
Ar
8 h Ar
O Ar
H
OH
OH Ar
O BF 3
N + N
N N +
H
CH 2 Ph CH 2 Ph
CH 2 Ph CH 2 Ph
Ar = 2,3-methylenedioxyphenyl 81–87%
(Continued)