Self Assembly Through Hydrogen Bonding: Preparation of a Supramolecular Aggregate Composed of Ten Molecules

✍ Scribed by Dr. John P. Mathias; Eric E. Simanek; Dr. Christopher T. Seto; Prof. George M. Whitesides

• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 584 KB
• Volume: 32
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/anie.199317661

✦ Synopsis

Boc l b L Boc J C Boc rac4 a-f rac-5 rac-7a (R = Ph) rac-7b (R = Me) Scheme 2. Reactions of the glycine derivative 1 b with electrophiles (only one enantiomer shown). After addition of one equivalent of the electrophile the yellow solution of the Li compound C decolorizes. Boc = ieri-butyloxycarbonyl. Compounds 4 are specified in Table 1.

sible stereoisomers (35: 1 and 7.6: 1 , respectively, according to NMR analysis). Again the depicted products having trans configuration are formed; the hydrolysis product of 7 b correlates to ah-threonine. Similar results are obtained when Z-protected alkoxydihydroimidazoles 1 a and 1 c are used (Z = benzyloxycarbonyl). Table 1 Alkylation of 1 b with alkyl halides. Only one diastereomer is formed according to analysis by NMR spectroscopy. The yields given refer to chromatographically purified (SiO,. penlanejether) samples Prod. RX Yield [%I Prod. RX Yield [Yo] 4a CHJ 99 4 e PhCH,Br 81 4c H,C=CHCH,Br 93 5 [a] C H J 98 4 b CH,CH,I 92 4 f 0,N-C,H,CH,Br 30 4d (CH,),CHI 92 6 [bl (CHdzCHl 62

[a] Prepared from 4e. [b] Prepared from 4b.