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Organic Synteses vol 70 - Meyers A.I.

Meyers A.I. , Boecman R.K. Organic Synteses vol 70 - John Wiley & Sons, 1992. - 163 p.
ISBN 0-471-57743
Download (direct link): organicsynthesesvol701992.pdf
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Iodo lactams are a useful, new class of difunctional compounds. Conversions of iodo lactams to N-acylaziridines,2'3 unsaturated lactams,2’4 azido lactams,2-3 amino lactams,2’3 hydroxy lactams,2 annulated lactams,2'5 and other derivatives have been described. Halo lactams have also been prepared from aspartic acid5 and glutamic
106
acid,6 from N-substituted unsaturated amides7-9 and imidates,10-12 and from unsaturated amides whose competing O-cyclization reaction is less favored.13’14
t. Department of Chemistry, Rutgers The State University of New Jersey. New Brunswick, NJ 08903.
2. Knapp, S.; Levorse, A. T. J. Org. Chem. 1988, S3, 4006, and references therein. Preliminary communication: Knapp, S.; Rodriques, K. E.; Levorse, A. T.; Ornaf, R. M. Tetrahedron Lett. 1985, 26,1803.
3. Knapp, S.; Levorse, A. T. Tetrahedron Lett. 1987, 28, 3213.
4. Knapp, S.; Levorse, A. T.; Potenza, A. J. J. Org. Chem. 1988, 53, 4773.
5. Salzmann, T. N.; Ratcliffe, R. W.; Christensen, B. G.; Bouffard, F. A. J. Am. Chem. Soc. 1980, 102, 6161.
6. Hardegger, E.; Ott, H. Helv. Chim. Acta 1955, 38, 312.
7. Biloski, A. J.; Wood, R. D.; Ganem, B. J. Am. Chem. Soc. 1982, 104, 3233.
8. (a) Rajendra, G.; Miller, M. J. Tetrahedron Lett. 1985, 26, 5385; (b) Rajendra,
G.; Miller, M. J. J. Org. Chem. 1987, 52, 4471; (c) Rajendra, G.; Miller, M. J. Tetrahedron Lett. 1987, 28, 6257.
9. Balko, T. W.; Brinkmeyer, R. S.; Terando, N. H. Tetrahedron Lett. 1989, 30, 2045.
10. Kano, S.; Yokomatsu, T.; Iwasawa, H.; Shibuya, S. Heterocycles 1987, 26, 359.
11. Takahata, H.; Takamatsu, T.; Mozumi, M.; Chen. Y.-S.; Yamazaki, T.; Aoe, K. J. Chem. Soc., Chem. Commun. 1987, 1627.
12. Kurth, M. J.; Bloom, S. H. J. Org. Chem. 1989, 54, 411.
13. Aida, T.; Legault, R.; Dugat, D.; Durst, T. Tetrahedron Lett. 1979,4993.
14. (a) Tamaru, Y.; Kawamura, S.; Tanaka, K.; Yoshida, Z. Tetrahedron Lett. 1984, 25, 1063; (b) Tamaru, Y.; Kawamura, S.-i. Bando, T.; Tanaka, K.; Hojo, M.; Yoshida, Z.-i. J. Org. Chem. 1988, 53, 5491.
107
TABLE
PREPARATION OF IODO LACTAMS
Entry
Unsaturated
Amide
lodo Lactam(s)
% Yield (cis/trans)
O
NH,
O
35
NH2
NH
35
O.
O I \\
0
Me
86
88
84(3:1)
Me
108
Entry Unsaturated Amide
lodo Lactam(s)
% Yield (cis/trans)
O.
Ph
O
nh2
-nh2
OCH2Ph
H2N^o
Ph
/-NH
yL
OCH2Ph
HN
O
Ph
I
OCH2Ph
a10-20% of starting amide was also recovered. b54% of crotonamide was also isolated. cOverall yield after separate desilylation.
88 (2:1)
86 (1:1)
109
Appendix
Chemical Abstracts Nomenclature (Collective Index Number); (Registry Number)
8-exo-lodo-2-azabicyclo[3.3.0]octan-3-one: Cyclopenta[b]pyrrol-2(1 H)-one, hexahydro-6-iodo-, (3aa,6a,6aa)- (11); (100556-58-9)
2-Cyclopentene-1-acetamide (10); (72845-09-1)
2-Cyclopentene-1-acetic acid (8,9); (13668-61-6)
Oxaiyl chloride (8); Ethanedioyl dichloride (9); (79-37-8)
Trimethylsilyl trifluoromethanesulfonate: Methanesulfonic acid, trifluoro-, trimethylsilyl ester (8,9); (27607-77-8)
no
(E)-1-BENZYL-3-(1-IODOETHYLIDENE)PIPERIDINE: NUCLEOPHILE-PROMOTED ALKYNE-IMINIUM ION CYCLIZATIONS
A. CH3^=-v^OH + CH3S02CI -sau- CH3^^^^0S02CH3
1
B. CH3β€”== .β€”^osOjCHj * pΒ»ch2nh2 CH,-=β€”^NH
2 ’'Ph
I
ry^CH3
N
3
Submitted by H. Arnold, L. E. Overman, M. J. Sharp and M. C. Witschel.1 Checked by Antje Griitzmann, Thomas Hache, and Ekkehard Winterfeldt.
1. Procedure
A. 4-Hexyn-1-yl methanesulfonate (1). An oven-dried, 500-mL, one-necked, round-bottomed flask equipped with a magnetic stirring bar is flushed with argon and 260 mL of dichloromethane is added (Note 1). The flask is sealed with a rubber septum inlet and cooled to ca. -10Β°C in an ice-salt bath. To this flask are added via syringe 11 mL (80 mmol) of triethylamine, 5.0 g (51 mmol) of 4-hexyn-1-ol (Note 2), and 4.3 mL (56 mmol) of methanesulfonyl chloride (Note 3). The resulting solution is
C. CH3β€”=β€”vaβ€žβ€ž + HCHO M
CampSOaH Ph
111
stirred for an additional 30 min and then quenched by adding 30 mL of ice-water. The organic layer is separated and washed successively with 1 M hydrochloric acid solution (30 mL), saturated aqueous sodium bicarbonate solution (30 mL), and brine (30 mL). The organic layer is dried over magnesium sulfate, filtered, and concentrated with a rotary evaporator to give 8.3-9.0 g (93-100%) of crude 4-hexyn-1-yl methanesulfonate (1) which was used directly in the next step (Note 4).
B. N-Benzyi-4-hexyn-1-amine (2). An oven-dried, 100-mL, one-necked, round-bottomed flask containing a magnetic stirring bar and a rubber septum inlet is flushed with argon and charged with 200 mg of sodium iodide. The crude mesylate 1, 40 mL of dimethyl sulfoxide (Note 5) and 10.9 g (102 mmol) of benzylamine are added via syringe. The resulting solution is heated in an oil bath at 47-53Β°C for 5 hr (Note 6) and then allowed to cool to room temperature. The reaction solution is poured into a separatory funnel containing 200 mL of aqueous 1% sodium hydroxide solution and the resulting mixture is extracted with ether (3 x 100 mL). The combined ether extracts are washed with brine (50 mL), dried over magnesium sulfate, filtered, and concentrated with a rotary evaporator. The residue (ca. 9 g) is purified by flash chromatography (ca. 300 g of silica gel using 1:1 hexane-ether containing 5% triethylamine as the eluent) (Note 7) to give 7.2-7.5 g (75-79% overall) of 2 as a colorless liquid (Note 8).
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