1H and 13C NMR sectra and one-bond 13C,13C coupling constants of (E)-2-alken-4-yn-1-ols, (E)-2-alken-4-yn-1-yl acetates and (E)-2-alken-4-yn-1-als;

✍ Scribed by Helmut Poleschner; Matthias Heydenreich

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 229 KB
• Volume: 35
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/(sici)1097-458x(199711)35:10<712::aid-omr159>3.0.co;2-x

✦ Synopsis

13C and some selected 1H NMR chemical shifts of conjugated (E)-enynes of the type of (E)-2-alken-4-yn-1-ols R = H, Me, Et, n-Pr, n-Bu, (E)-2-alken-4-yn-1-yl acetates (RCyCCHxCHCH 2 OH ; SiMe 3 ), R = H, Me, Et, n-Pr, n-Bu) and (E)-2-alken-4-yn-1-als (RCyCCHxCHCHxO ; (RCyCCHxCHCH 2 OAc ; R = Et, n-Pr) and of (2Z,4E)-deca-2,4-dien-6-yne as a conjugated (Z,E)-dienyne were measured. The unequivocal assignment of the 13C NMR chemical shifts is based on the application of standard techniques such as H,H-COSY, C,H-COSY and APT and, above all, on the investigation of the C,C connectivities by determination of the one-bond 13C,13C coupling constants These coupling constants show typical values for the di †erent structur-1J C,C . al fragments. The e †ect of increments of the alkyl group on the resonances of the acetylenic carbon atoms are compared with those of the n-alkynes. The shift e †ects observed on going from (E)-2-alken-4-yn-1-ols to (E)-2alken-4-yn-1-als are discussed in comparison with results from other classes of compounds. 1997 John Wiley & ( Sons, Ltd.