The Diels-Alder Reaction

M
	R	O		PhMe, 110 C, 6 h	R	O
		R1				R1
		+		53%
TMSO		O	R	2	TMSO	O R2
						H

R = H, OMe; R1 = CO2Bn, CO2t-Bu; R2 = Ph, p-MeOC6H4

M

							R4
MeO	OMe						O
			O			MeOH, 50 C
	O			R
		+	R4		6	R5	R1
						0.5−3 h, 36−80%
R1	R3		R5			R2	R3
	R2
							O
	DAIB					5 furans
	MeOH					R4, R5, R6 = H, Me, CO2Me
	OMe					R4-R5 = -CH=CH-CH=CH-

OH

R6

OMe

OMe

R1 R3

R2

R1 = H, CO2Me, COMe; R2 = H, CO2Me; R3 = H, OMe

	H	O	HOH2C
		Si
			Si
O		H
Si	PhH, 170 C	Li	1.5
		+	THF
		O
	H		HOH2C
		Si
			Si
		H
			1
			overall yield: 67%

M

% # &

R				NC	CN		R				R
						PhMe, 25−110 C	CN				CN
				+						+
						0.5−5 d, 28−96%	R1				R2
				NC	CN		R2NC CNCN				R1NC CNCN
R1 R2
R = H,				; R1	= Me, n-Bu, SiMe3; R2 = H, Me, n-Pn,
		S		S			MOMO

3 dienophiles; 5 vinylallenes

+	SO2	Br	PhMe, 90 C, 24 h
			Ts
			94%
6 dienes			Br

M

		SPh			O
	PhS	H				H
	Cl2C6H4, 180 C, 18 h	H	H	+	H	SPh
						H
	i-Pr2EtN					53%
		O				H
				+	O
O		15%				SPh
					H
						H
						21%

M

O		OMe			O	R
	R
		PhMe, 25−110	C
		+
O		20−48 h, 38−85%			O	O
		OSBT
						H

R = CN, COMe, CO2Et, SO2Ph 6 dienes

M
% # # &
R1		Z				R1
					O	Z
TBMDSO			PhH or CHCl3
	+
			Rfx, 1−18 h, 0−72%			N
N OR3					H
		CO2Me				CO2Me

R2

R2

R1 = H, Me, Bu, Ph, F, Cl; R2 = H, Me; R3 = TBDMS, i -Pr, Et; Z = H, Me, CO2Me 9 dienes, 8 dienophiles

% # &

N		N	SnBu3			SnBu3
				DCM, r.t. or MeCN, 80 C	N
			+			N
N		N		0.1−28 d, 71−95%		+
					N	N
	Ar		H			SnBu3
					Ar	Ar

18 aryl-1,2,4,5-tetrazines

	R3			R3
		r.t., 10 h	S	R2
	R2
	RCS2R1 +	30−85%	R	R2
	R2		R1S

R = CF3, C3F7; R1 = Et, Bn

2 dienes: R3 = H, R2 = Me; R2 = H, R3 = OSMT

M

O

( )n

n = 1, 2

6 substrates

hn, Pyrex

66−80%

O

H

( )n

H H H

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