A series of novel 1-methylpropargyl-N-alkylcarbamates, HC C-(R)-CH(CH3)OCONHCH2-CO2CH2CH2](R)-1HC C-(S)-CH(CH3)OCONHCH2CO2CH2CH2[(S)-1], HC C-(S)-CH(CH3)-OCONH-(R)-CH(CH3)CH2CH2CH2CH2CH2CH3[(s),(R)'-2], HC C-(S)-CH(CH3)OCONH-(R)-CH(CH3)CO2-CH2CH2CH3[(S),(R)-3], HC CCH2OCONH-(R)-CH(CH3)CO2CH2CH2CH3 [(R)'-4, HC CCH2OCONH-(S)-CH(CH3)CO2CH2CH2CH3[(S)'-4], and HC CCH2OCONHCH2CO2CH2CH2CH3 (5) were synthesized and r olymel Ind using (nbd)Rh+[eta(6)-C6H5B-(C6H5)(3)] (nbd = bornachene) as a catalyst Substituted cis-stereoregular polyacetylencs with moderate molecular weights were obtained in good yields Polyl(R)-1.1, polyl(S)- I, polyl(S),(RY-2), and poly[(5),(R)1-31 exhibited laige optical rotations (vertical bar[alpha](D)vertical bar= 344 degrees -508 degrees), clear CD signal; (Ar = 4 8-7 0 M-1 cm-1) in CliC11, and Inch viscosity indices (0 82-0 87), demonstrating the formation or-helical structures with predominantly one-handed sciew sense, which wei c stable up to 55 degrees C in the solvent The solution state IR measurement confirmed the presence of mtramolecular hydrogen bonding between the pendent carbamate groups of the polymers Chiral amplification was observed in chiral/achiral [(S)-1/5] and R/S [(R)-I /(S)-1] copolymei izations Conformational analysis revealed that the polymers adopt a tightly twisted helical conformation with a dihedral angle of 70 degrees at the single bond on the main chain The molecular mechanics calcul.ition and X-ray diffraction measurement suggested that the diameter of the helix is 25 and 17 angstrom, respectively.