28.12.2013 Views

preface to fifteenth edition

preface to fifteenth edition

preface to fifteenth edition

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

SPECTROSCOPY 7.81<br />

TABLE 7.34<br />

Raman Frequencies of Other Double Bonds (Continued)<br />

GroupBand, cm<br />

1<br />

Remarks<br />

C"N9 bonds (continued)<br />

Hydrazones<br />

H<br />

H<br />

C"N9N<br />

1660–1610 (s–vs)<br />

R 1<br />

R 2<br />

Imido ethers<br />

O<br />

C"NH<br />

1658–1648 NH stretching at 3360–3327<br />

cm 1<br />

Semicarbazones and thiosemicarbazones<br />

H<br />

C"N9N NH 2<br />

C<br />

O (or S)<br />

1665–1642 (vs)<br />

1620–1610 (vs)<br />

Azo compounds 9N"N9<br />

Aliphatic. Thiosemicarbazones<br />

fall in lower end of range.<br />

Aromatic derivatives<br />

9N"N9 1580–1570 (vs) Nonconjugated<br />

1442–1380 (vs) Conjugated <strong>to</strong> aromatic ring<br />

1060–1030 (vs) CN stretching in aryl compounds<br />

Nitro compounds N"O<br />

Alkyl nitrites 1660–1620 (s) N"O stretching<br />

Alkyl nitrates 1635–1622 (w–m) Asymmetric NO 2 stretching<br />

1285–1260 (vs) Symmetric NO 2 stretching<br />

610–562 (m) NO 2 deformation<br />

Nitroalkanes<br />

Primary<br />

Secondary<br />

1560–1548 (m–s)<br />

1395–1370 (s) Sensitive <strong>to</strong> substituents attached<br />

<strong>to</strong> CNO 2 group<br />

915–898 (m–s)<br />

894–873 (m–s)<br />

618–609 (w)<br />

640–615 (w) Shoulder<br />

494–472 (w–m) Broad; useful <strong>to</strong> distinguish<br />

from secondary nitroalkanes<br />

1553–1547 (m)<br />

1375–1360 (s)<br />

908–868 (m)<br />

863–847 (s)<br />

625–613 (m)<br />

560–516 (s) Sharpband

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!