Organic Reaction Mechanisms 1997

"

O

O

O

O

OH

Ph

hν

Ar

Ar

Ph

Ar

Ph

DABCO

O

(23)

(24)

(25)

Ar = p-NCPh

K $

K

Ar								Ar
			Ar
	DCA		.		DCA
			.
Ar				Ar				Ar
(26)			(28)		(27)
Ar = 4-MeOC6H4

SCHEME 5

R	R		O
Si
			Si
			O
(29)		(30)
R = mesityl

		HO		Ph			O			Ph
1			2
		Ph	3	N
							Ph			N
					O					O
(31)			(32)							(33)

# J

	+ .
	hν										OCH3
(34)					(35)
H OCH3				H OCH3				H OCH3

(37) (25%)

(36) (15%)

(35) (30%)

SCHEME 6

J J

K

Ar

OH

O

(38)

(39)

				K

K K

J

#

M

K

Ph

Ph

Ph

Ph

N

Ph

hν

N

Ph

N

Ph

DCA

+ .

Ph

Ph

CN

(40)

(42)

(41)

SCHEME 7

M

	Pri					Et
							N
	N		N
But	N	N	Pri		N
			But				S		SO3NH4
		(43)						2
								(44)

J

J

J

J

J

#

#

#

$

#

			O
N	Ph	R1				R1
O						R1

(45)

R2 (46) R1 = H (47) R1 = Me

J

#

NC	CN	Ar		Ar		OH + Ar	O
					+ Ar
Ph	Ph	Ar
Ph	Ph
(48)		(49)

M M

#

S

XX S

(50)

X = H, Me, OMe, Cl, NO2

J

# #

J

J #

J

H2N				+ .
				NH2
(51)			(52)

#

J

M

J

				+					R
R			R	N
10
1				+					N+
9
(53)				(54)
R= H, Me

(55)

SCHEME 8

# M

J

J

J

$ $

M

$

#

#

#

M

M

X

	2+					+ .	4
							5
	+
(56)	(57)	(58)					(59)

#

K

M

+ .

Mes		O		X		Mes	O			O
							.			R
Mes		R				Mes	R

(63)

Mes

(60) X = H, COR′, SiR′3, TiCp2Cl, PO(OR′)2

(65)

(61) X = H, CONHBut

(62) X = CO2R′

R = Me, But, Ph, Mes

O

R

Mes

(64)

SCHEME 9

M

#