Organic Reaction Mechanisms 1997

X

2n-BuLi

Li

ET

E

N+

N+

N+

TMEDA

Li

N

H

N

N

E

O

O

O

O–

O–

O–

(91)

(92)

(93)

SCHEME 5

N

OMe

N

OMe

2equiv. LDA

R2

R1

O

R2

THF

R1

(Z)-(94)

OH

(Z)-(95)

a; R1 = p-tolyl, R2 = Ph

Me

b; R1 = Ph, R2 = CH=CH

2

R2

O

N

OMe

Li

R2

N

R1

O

R1

O

SCHEME 6

n-BuLi

–

–

H2O(D2O)

THF–HMPA

–78 °C

H

(96)

(97)

(98)

(99) Y = H Y

(99)-d, Y = D

0 °C

–

–

H2O

H

(100)

(101)

(102)

SCHEME 7

J

J

Ar

Ar

Ar

Ar

+ HO–

k′1

OH

k′–1

O

(103)

O

O

O–

(104)

Ar =XC6H4

k′–2

k′2

H

Ar

Ar

Ar

Ar

k′3

fast

–

Ar

CO

CO2–

Ar

CO

CO2H

–O

CO2H

(107)

(106)

(105)

SCHEME 8

J

$

M

M $ $

M

X

O

X

OH

–

k1

O–

+ HO

k–1

O

O

Y

Y

(108)

(109)

X

OH

k–2

k2

X

OH

–

k3

O

O

Y

k–3

O

Y

O–

(111)

(110)

+H2O

k4

X

H

X

OH

CHO

fast

O + HO–

–H2O

CO2–

Y

Y

O

(113)

(112)

SCHEME 9

D D

–O

(CH2)n

Ph

Ph D

(114)-d3

Reactant(114)-d3

a; (n = 2) b; (n = 3) c; (n = 4) d; (n = 5)

–O

H2O quench

Ph

D

(CH2)n

d1-ketone

intermol.

Ph

C

H-transfer

H

D

D

DMSO

O

D

Ph

(CH2)n

–C

Ph

D

intramol.

(115)

H-transfer –O

H2O quench

Ph

D

(CH2)n

d2-ketone

Ph

C

D D

Product[d1]:[d2]	k114/k114-d3
65:35	2.47

––

42:58	1.37
95:5	1.43

SCHEME 10

J

N	N	+2e	–		–	R1		E	+	E	R1
						R2					R2
		–Bt
N					R3						R3

R3 R1 R2

(116)

a; R1, R2 = Ph, R3 = H

b; R1 = Ph, R2, R3 = H

c; R1 = CH CH2, R2, R3 = H

SCHEME 11

K

K

K

K

K

J

K

$ $ $ $

R1 X R2	(117) X = O
–	(118) X = NR4
R3

J

J

M

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